Lock monitoring in Postgres: Find blocking queries in a lock tree with pganalyze
01 December, 2022Postgres databases power many mission critical applications, and applications expect consistent query performance. If even a single query takes longer than expected, it can lead to unhappy users, or delayed background processes. We can use to debug a slow query, but there is one Postgres problem it won't tell us about: Blocked queries. You may also know this as "blocked sessions" from other database systems. This is when one query holds a lock on a table and the other is waiting for those locks…
Continue readingCreating custom extensions on Amazon RDS and Aurora with pg_tle
01 December, 2022In today's episode 46 of 5mins of Postgres, we talk about trusted language extensions and how to use them on Amazon RDS and Aurora, as well as the new pg_tle extension. We also take a look at pg_tle's support for the "password check hook". Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Trusted language extensions for Postgres Postgres CREATE EXTENSION pg_tle: Postgres Trusted Language Extensions Using the pg_tle Trusted Language Extension…
Continue reading5mins of Postgres E45: IN lists vs ANY operator: Bind parameters and performance
24 November, 2022Today, we're going to talk about the difference between the ANY and the IN operator in Postgres, how they differ in performance, and why you might use one or the other. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres security: IN lists vs. ANY operator Using the ANY operator and bind parameters Postgres performance: IN lists vs. ANY operator Allow hash lookup for IN clauses with many constants Postgres index not used with = ANY() but…
Continue reading5mins of Postgres E44: Reducing replication lag with maintenance_io_concurrency in Postgres 15
17 November, 2022Today, we're talking about reducing replication lag by setting the maintenance_io_concurrency setting in Postgres 15. We're also talking about true asynchronous I/O in Postgres and how to use "recovery prefetch". Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Using maintenance_io_concurrency to reduce replication lag How to use maintenance_io_concurrency in Postgres 15 Reducing Postgres replication lag True async I/O in Postgres What we have…
Continue reading5mins of Postgres E43: Logical replication in Postgres 15 & why the REPLICA IDENTITY matters
10 November, 2022Today, we're going to talk about logical replication improvements in Postgres 15. In particular, we’ll talk about improvements to data filtering, why the REPLICA IDENTITY is important, and how logical replication deals with errors. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres 15 logical replication improvements Logical replication in Postgres 15: Defining which data gets replicated in the replication stream Postgres data filtering…
Continue reading5mins of Postgres E42: A surprising case of very large integers causing a Sequential Scan
03 November, 2022Today, we talk about a surprising case of a very large integer causing a Sequential Scan in Postgres. There are cases when Postgres decides to not use an index, but instead opts for a Sequential Scan. This can cause some very real performance problems. Let’s have a look at why it does this and ways to resolve this issue! Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Circumvent bigints being cast to numeric values to avoid slow sequential…
Continue reading5mins of Postgres E41: Tuning shared_buffers for OLTP and data warehouse workloads & is 25% of RAM a good choice?
27 October, 2022In this episode of 5mins of Postgres, we’re going to talk about tuning shared_buffers, benchmarking with pgbench, TPROC-C and TPROC-H, and whether using 25% of RAM is a good choice. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Tuning shared_buffers in Postgres Benchmarking Postgres performance Benchmarking Postgres with pgbench Using pg_buffercache TPROC-C and TPROC-H benchmarks in Postgres Conclusion What we have discussed in this episode…
Continue reading5mins of Postgres E40: How to debug slow Postgres UPDATEs and bloated tables with auto_explain & page_inspect
20 October, 2022Today, we talk about why Postgres UPDATEs are getting slower over time, HOT updates, auto_explain, the pageinspect extension, and reasons why VACUUM won’t remove dead rows from a table. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Debugging slow Postgres UPDATEs and bloated tables Understanding Postgres queries with auto_explain Using log_min_duration and log_timing Understanding Postgres UPDATE and VACUUM HOT pruning in Postgres…
Continue reading5mins of Postgres E39: Postgres 15 release, and 6 tips for managing indexes
13 October, 2022Today, we're going to talk about the Postgres 15 release, and six findings to improve how you manage your Postgres indexes. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres 15 is released Managing Postgres indexes Each individual index has storage and write costs Postgres can choose different ways to query indexed data Combined indexes versus multi-column indexes in Postgres Column placement in multi-column indexes Use sorted indexes…
Continue reading5mins of Postgres E38: When to use BRIN indexes in Postgres, tuning pages_per_range and determining correlation with pg_stats
06 October, 2022In this article and video, we talk about tuning a Postgres BRIN index and how to decide whether to use BRIN based on pg_stats statistics and the correlation column. We also talk about the impact block ranges can have and a visual model on how to think about BRIN indexes. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. How to tune BRIN indexes to speed up Postgres performance Understanding BRIN indexes Block sizes for BRIN indexes Multi-column…
Continue reading5mins of Postgres E37: New in Postgres 15: Logical replication column filters & database-wide ICU collations
29 September, 2022Today, we talk about new features in Postgres 15, including logical replication improvements and database wide ICU locales. In case you're not aware, Postgres 15 rc1 is around the corner and we can expect the final release of Postgres 15 within the next couple of weeks. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Using column lists in logical replication to filter data Skipping data to reduce network traffic, and data relevancy Database…
Continue reading5mins of Postgres E36: Optimizing Postgres query throughput in Python using pipeline mode and psycopg 3.1
22 September, 2022Today, we're going to talk about the new psycopg driver for Python. We're also going to talk about pipeline mode in psycopg and how it works. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. psycopg 3.1 for Python and Postgres Pipeline mode in psycopg 3.1 and Postgres Using connection.pipeline in psycopg Getting 2x - 10x better Postgres performance with pipeline mode What we have discussed in this episode of 5mins of Postgres Transcript Let's…
Continue reading5mins of Postgres E35: How to run EXPLAIN on normalized queries from pg_stat_statements using plan_cache_mode
15 September, 2022In today’s episode we're going to talk about how to run EXPLAIN on a normalized query from pg_stat_statements and how to get the generic query plan. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres EXPLAIN plans and pg_stat_statements What is pg_stat_statements in Postgres Can we use EXPLAIN by passing null? Using plan_cache_mode in Postgres to force the query planner to use a generic plan What we have discussed in this episode of…
Continue reading5mins of Postgres E34: Making the most of Parallel VACUUM and why SQL/JSON was pushed out to Postgres 16
08 September, 2022In this episode, we're walking through parallel VACUUMing in Postgres 13 and newer. We're also going to talk about the unfortunate fact that SQL/JSON won't be in Postgres 15. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. VACUUM and Parallel VACUUM in Postgres Postgres VACUUM: The 4 phases Parallel VACUUM in Postgres Understanding VACUUM parameters in Postgres The max_worker_processes Postgres VACUUM parameter The min_parallel_index_scan…
Continue reading5mins of Postgres E33: Postgres on Kubernetes, choosing the right operator, and handling major version upgrades
01 September, 2022Today, we're gonna talk about Postgres on Kubernetes, how it has improved over the years and two improvements to operators in recent times. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres and Kubernetes Using PostgreSQL Operators Importing an Existing Postgres Database to Kubernetes with CloudNativePG Postgres Upgrades with the PGO operator What we have discussed in this episode of 5mins of Postgres Transcript Let's have a look…
Continue reading5mins of Postgres E32: Benchmarking and improving query network latency using tc, COPY and pipeline mode
25 August, 2022Today, we're gonna talk about network latency, how it impacts your query performance and how to improve it by using pipeline mode or COPY in Postgres. We also take a look at traffic control with the Linux tc tool. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Improving network latency in Postgres Using tc (traffic control) in Linux and Postgres Using \timing in psql COPY vs. INSERT in Postgres Using COPY to continuously send data to the…
Continue reading5mins of Postgres E31: Postgres security patch release, spotting vulnerable extensions and securing the public schema
18 August, 2022Today, we walk through the latest Postgres patch releases and a security bug that got fixed. We'll also talk about extension security in Postgres, as well as the public schema and a change in Postgres 15 to make it more secure. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Latest PostgreSQL patches Extension scripts replace objects not belonging to the extension: bug fix Use pgspot to detect problematic vulnerabilities in PostgreSQL…
Continue reading5mins of Postgres E30: Postgres performance puzzle, Linux readahead and tuning effective_io_concurrency
11 August, 2022Today, we're going to talk about an interesting Postgres performance puzzle by Jeremy Schneider, Linux readahead and how to tune effective_io_concurrency. The default Linux readahead setting assumes sequential scans ahead, but you might want to change it, together with effective_io_concurrency, which tunes how much Postgres is telling the Linux Kernel to look ahead. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres performance tuning…
Continue reading5mins of Postgres E29: Postgres lock conflicts on Amazon Aurora & tuning max_standby_streaming_delay and hot_standby_feedback
04 August, 2022Today, we're talking about Postgres lock conflicts on Amazon Aurora and tuning and , why you should implement retry logic with Aurora and how you can avoid query conflicts on Postgres with Amazon Aurora's fast clones. We’ll also look at an effective setup from the Twitch team for these settings. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. The difference between Amazon Aurora and Amazon RDS The downsides of Amazon Aurora’s data sharing…
Continue reading5mins of Postgres E28: Row Level Security in Postgres, security invoker views and why LEAKPROOF functions matter
28 July, 2022Today, we're going to talk about Postgres Row Level Security, the BYPASSRLS attribute, security invoker views, and Postgres performance problems when using LEAKPROOF functions and Row Level Security policies. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Using Postgres Row Level Security for multi-tenant databases Row Level Security in Postgres and the BYPASSRLS attribute Using Row Level Security in Postgres together with a view Security…
Continue reading5mins of Postgres E27: Waiting for Postgres 16 - Make subquery alias optional in FROM clause
21 July, 2022Today, we are talking about a change in Postgres 16, that removes the alias requirement for subqueries in FROM. This may seem like a very obscure problem, but it's actually a very common issue for people that either migrate to Postgres, for example from Oracle to Postgres, or who are new to Postgres and run into this error. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Fixing the "subquery in FROM must have an alias" error The first attempt…
Continue reading5mins of Postgres E26: New in Postgres 15 - NULL handling in UNIQUE constraints & Parallel DISTINCT
14 July, 2022Today, we are talking about two new features in Postgres 15. First of all, we're going to talk about the new unique constraint NULLS NOT DISTINCT option, and then we'll talk about the SELECT DISTINCT performance improvements. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. UNIQUE constraints and NULL values The behavior in older Postgres versions Rejecting duplicate NULL values in Postgres 15 with NULLS NOT DISTINCT The upcoming SQL Standard…
Continue reading5mins of Postgres E25: Postgres lock monitoring, LWLocks and the log_lock_waits setting
07 July, 2022Today, we are talking about Postgres locking. When it is concerning, what lightweight locks are, as well as the setting in Postgres. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Postgres lock monitoring with the pg_locks view Counting how many locks are not granted Finding the blocking process when a query is waiting for a lock Understanding lightweight locks (LWLocks) Tracking locking problems over time with log_lock_waits Should I…
Continue reading5mins of Postgres E24: Tuning the Postgres statistics target & understanding selectivity for spatial indexes
30 June, 2022Today, we are talking about tuning the Postgres statistics target, why it is 100 and how that number was derived, and Postgres selectivity, specifically selectivity for spatial indexes. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Tuning the Postgres statistics target Changing the Postgres statistics target on a per column basis Selectivity in Postgres Selectivity for spatial indexes in Postgres Amazon Aurora support for Postgres 14 What…
Continue reading5mins of Postgres E23: Fuzzy text search & case-insensitive ICU collations in Postgres
23 June, 2022Today, we're going to talk about fuzzy text search in Postgres with LIKE/ILIKE, trigrams, levenshtein distances, as well as case-insensitive pattern matching. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Fuzzy text search in Postgres Searching with LIKE/ILIKE Searching with regular expressions Full-Text search in Postgres Searching with trigrams Using the levenshtein distance to search in Postgres Understanding case-insensitive pattern…
Continue reading5mins of Postgres E22: Reducing AWS Aurora I/O costs with table partitioning & understanding partition pruning
16 June, 2022Today, we're going to talk about using partitioning to reduce AWS Aurora I/O costs, pg_partman, and how partition pruning speeds up query performance. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Using Postgres partition pruning to reduce AWS Aurora I/O costs Improving Postgres query performance and reducing I/O costs with partition pruning Partition Pruning in PostgreSQL Fixing the CREATED INDEX CONCURRENTLY or REINDEX CONCURRENTLY bug on…
Continue reading5mins of Postgres E21: Server-side backup compression with LZ4 and Zstandard in Postgres 15, and the removal of exclusive backup mode
09 June, 2022In today’s episode 21, we're going to talk about backup improvements in Postgres 15. Postgres 15 beta1 came out a couple of weeks ago and we’re looking into LZ4 and Zstandard compression, as well as the removal of the exclusive backup mode. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Removal of the exclusive backup mode in Postgres 15 Using Server-Side LZ4 Backup Compression in Postgres 15 Using Parallel Server-Side Backup Compression in…
Continue reading5mins of Postgres E20: An important bug in Postgres 14 with REINDEX / CREATE INDEX CONCURRENTLY, and using the amcheck extension
02 June, 2022Today, we're going to talk about an important indexing bug that was discovered in Postgres 14 and how you can verify if this affects you with the amcheck extension. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. REINDEX / CREATE INDEX CONCURRENTLY bug in Postgres 14 Understanding the amcheck extension in Postgres Using the bt_index_check function in amcheck for Postgres What we have discussed in this episode of 5mins of Postgres Transcript…
Continue readingAn automatic indexing system for Postgres: How we built the pganalyze Indexing Engine
01 June, 2022Indexing is hard. Most people who have worked with databases will agree that regardless of how you do it, creating the right indexes on your database requires thought and detailed analysis. It's not something to be taken lightly. If you don't create the right indexes, your queries will be slow, and if you create too many indexes, your writes on busy tables will be slowed down significantly. But even if you know how to do it, indexing takes a lot of effort. And this has gotten more complex with…
Continue readingA balanced approach to automatic Postgres indexing: The new version of the pganalyze Index Advisor
01 June, 2022Historically, index creation, tuning and maintenance has been the task of database administrators who had a detailed understanding of the different queries used by applications. The fast-moving pace of modern application development, combined with a move to the cloud, has shifted the responsibility of indexing to application developers - without giving them the right tools. Application developers today spend a lot of time manually creating indexes for their Postgres queries, reviewing database…
Continue reading5mins of Postgres E19: Speeding up sort performance in Postgres 15
26 May, 2022Today, we're going to talk about four specific improvements made in Postgres 15 that help speeding up sort performance: Sorting a single column Reducing memory consumption by using a different memory allocator New specialized sort routines for common data types Replacing the algorithm that's used for splitting up sorts to disk when they exceed the "work_mem". Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Four improvements that help speeding…
Continue readingDesign at pganalyze: How we use design principles to develop new features and products
24 May, 2022At pganalyze, we know attention and time is very valuable and being respectful of it will allow everyone on the team to think deeply and do high-quality work. That’s why we run only a few standing meetings. It’s one actually. A weekly meeting on Tuesdays. Most of our active working time goes into product development, infrastructure improvements, and working with customers. Apart from that, it is on each team member to organize and schedule working sessions, support triages, or workshops. We are…
Continue reading5mins of Postgres E18: Partition pruning, prepared statements and generic vs custom query plans
19 May, 2022In today’s episode 18, we'll talk about partition pruning and prepared statements in Postgres and run a performance test using the pgbench tool. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Performance of prepared statements with partitioning in Postgres Understanding prepared statements in Postgres Partition pruning in Postgres What we have discussed in this episode of 5mins of Postgres Transcript Let's dive in. Performance of prepared…
Continue reading5mins of Postgres E17: Demystifying Postgres for application developers: A mental model for tables and indexes
12 May, 2022Today, we're going to talk about demystifying database performance for developers. This blog post by Christopher Winslett talks about how to think about your database as an application developer and what kind of mental model you can have to think effectively about how to use indexes and other data structures in your database. We will talk about Postgres Tables, Indexes, Index Cardinality, Table scans, and more! Share this episode: Click here to share this episode on twitter and subscribe to our…
Continue reading5mins of Postgres E16: Incremental Materialized Views with pg_ivm and Looking Ahead to Postgres 15 Beta 1
05 May, 2022Today, we're going to talk about incremental view maintenance, as well as the upcoming Postgres 15 beta release. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Using Incremental Materialized Views with pg_ivm Performance of Incremental Materialized Views with pg_ivm A first look at Postgres 15 Beta 1 What we have discussed in this episode of 5mins of Postgres Transcript Let's take a look! Using Incremental Materialized Views with pg_ivm So…
Continue readingThe Unexpected Find That Freed 20GB of Unused Index Space
04 May, 2022How to free space without dropping indexes or deleting data Every few months we get an alert from our database monitoring to warn us that we are about to run out of space. Usually we just provision more storage and forget about it, but this time we were under quarantine, and the system in question was under less load than usual. We thought this is a good opportunity to do some cleanups that would otherwise be much more challenging. To start from the end, we ended up freeing more than 70GB of un…
Continue reading5mins of Postgres E15: Tuning Postgres' Deterministic Query Planner, Extended Statistics and Join Collapse Limits
28 April, 2022Today, we'll talk about optimizing with the Postgres deterministic query planner, have a look at using extended statistics, and show how to tune Join collapse times. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Optimizing with Postgres’ deterministic query planner Setting costs for page access Using Extended Statistics in Postgres CREATE STATISTICS and the dependencies statistics type in Postgres Tuning Join Collapse Limits in Postgres…
Continue reading5mins of Postgres E14: HOT Updates vs Bottom-Up Index Deletion in Postgres 14
21 April, 2022Today, we're going to talk about bottom-up index deletion for B-tree indexes, Postgres pages, Postgres page splits in B-Tree indexes, the bt_page_items function, and how Bottom-Up Index Deletions compare to HOT updates. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. Comparing HOT Updates and Bottom-Up Index Deletion Understanding Postgres pages Postgres page splits in B-Tree indexes Bottom-Up Index deletion in Postgres to avoid page splits…
Continue reading5mins of Postgres E13: New SQL/JSON and JSON_TABLE features in Postgres 15
14 April, 2022In today's video, we take a look at the SQL/JSON features in Postgres 15. Postgres 15 will most likely be released in September or October, so it's still quite a way until we can actually use this on a production server. However, a couple of days ago, the Postgres 15 feature freeze occurred, which means we now have a good sense for which functionality will make it into this next Postgres release. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel…
Continue reading5mins of Postgres E12: The basics of tuning VACUUM and autovacuum
07 April, 2022Today, we're going to talk about tidying up with VACUUM. Now, as the Postgres Weekly newsletter put it, we can't go a month without covering VACUUM in some way or another. If you recall a few weeks ago, we last talked about "dead tuples not yet removable" and what is essentially a very specific VACUUM problem that causes VACUUM to stall and not make progress. You can find the episodes about this here: 5mins of Postgres E7: Autovacuum, dead tuples not yet removable, and the Postgres xmin horizon…
Continue readingHow Postgres Chooses Which Index To Use For A Query
01 April, 2022Using Postgres sometimes feels like magic. But sometimes the magic is too much, such as when you are trying to understand the reason behind a seemingly bad Postgres query plan. I've often times found myself in a situation where I asked myself: "Postgres, what are you thinking?". Staring at an EXPLAIN plan, seeing a , and being puzzled as to why Postgres isn't doing what I am expecting. This has lead me down the path of reading the Postgres source, in search for answers. Why is Postgres choosing…
Continue reading5mins of Postgres E11: MERGE in Postgres 15, and how it compares to INSERT ON CONFLICT
31 March, 2022Today, in episode 11 of our series, we are taking a look at the command and how it differs from the command. Share this episode: Click here to share this episode on twitter and subscribe to our YouTube channel. MERGE in Postgres 15 How the MERGE command works in Postgres Why there is an INSERT ON CONFLICT command in Postgres What we have discussed in this episode of 5mins of Postgres Transcript Let's get started. MERGE in Postgres 15 Earlier this week, the command was merged into the Postgres…
Continue reading5mins of Postgres E10: max_wal_size, Postgres full page writes and UUID vs BIGINT primary keys
24 March, 2022In today’s episode 10, we'll take a look at max_wal_size, full-page writes and why you might want to choose BIGINT instead of a UUID for your primary key column. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Tuning max_wal_size in PostgreSQL What is max_wal_size Optimizing max_wal_size and checkpoint_timeout The impact of full-page writes in Postgres Using UUID vs BIGINT data types for primary keys What we have discussed in this episode of 5mins of…
Continue reading5mins of Postgres E9: PostGIS vs GPUs, tuning parallel queries, and automating Citus extension benchmarks with HammerDB
17 March, 2022In this episode, we'll talk about PostGIS versus GPU performance for spatial queries and also take a look at using HammerDB and custom automation scripts to benchmark the Citus extension. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript Looking at PostGIS vs. GPU for Performance and Spatial Joins The importance of automating performance benchmarks Using HammerDB to drive a TPC-C or TPC-H benchmark What we have discussed in this episode of 5mins…
Continue reading5mins of Postgres E8: Postgres Auditing: Table triggers with supabase vs the pgAudit extension
10 March, 2022Today, we'll take a look at Postgres auditing. We'll look at two different approaches: Using triggers in Postgres Using the pgAudit extension Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript Using triggers in Postgres for Postgres Auditing Using the pgAudit extension for Postgres Auditing What we have discussed in this episode of 5mins of Postgres Transcript Let's jump in! Using triggers in Postgres for Postgres Auditing Today’s episode was…
Continue reading5mins of Postgres E7: Autovacuum, dead tuples not yet removable, and the Postgres xmin horizon
03 March, 2022Today, we'll talk about autovacuum, dead tuples not yet removable, and what the xmin horizon in Postgres does. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript Vacuuming dead tuples not yet removable in Postgres When vacuum doesn’t remove dead rows from a table 1) Long running transactions 2) Replication slots 3) Prepared transactions What we have discussed in this episode of 5mins of Postgres Transcript Let's get started! Vacuuming dead tuples…
Continue reading5mins of Postgres E6: Optimizing Postgres Text Search with Trigrams and GiST indexes
24 February, 2022Today, we're looking at optimizing Postgres text search with trigrams and take a closer look at GiST indexes. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript Improving Postgres text search performance with trigrams Understanding the siglen parameter How GiST indexes work What we have discussed in this episode of 5mins of Postgres Transcript Let's have a look together! Improving Postgres text search performance with trigrams Trigrams in general…
Continue reading5mins of Postgres E5: Finding the root cause of high CPU utilization in Postgres with EXPLAIN and the Linux perf command
17 February, 2022Today, we'll take a look at a hairy Postgres incident and how we can use Postgres EXPLAIN and the Linux perf command to debug high CPU utilization in Postgres. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript Debugging a 100% CPU utilization spike with EXPLAIN and perf Comparing the old system vs. the new system Going one step deeper: Linux system level tools Profiling with the Linux perf utility set CPU Profiling with run_xcpu by Tanel Poder…
Continue reading5mins of Postgres E4: Writing your own custom Postgres aggregates with Rust or raw SQL
10 February, 2022Today we'll take a look at how to write custom aggregates in Postgres using either Rust or raw SQL. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript Using pgx to write a Rust extension for Postgres that runs custom aggregate code Using raw SQL to implement harmonic mean and geometric mean in Postgres Using aggregation in Postgres to refine hyperfunctions design What we have discussed in this episode of 5mins of Postgres Transcript Let's get…
Continue reading5mins of Postgres E3: Postgres performance cliffs with large JSONB values and TOAST
03 February, 2022Today, we're going to talk about JSONB and how JSONB performance can behave badly when the JSONB value exceeds the two kilobyte limit where Postgres starts storing data in TOAST. Share this episode: Click here to post to twitter and subscribe to our YouTube channel. Transcript How Postgres stores data: Large JSON value query performance PostgreSQL physical storage Understanding JSONB performance What we have discussed in this episode of 5mins of Postgres Transcript Let's dive right in! How…
Continue reading5mins of Postgres E2: Using unnest(..), generate_series(), and PostGIS
27 January, 2022Today, we're gonna look at a few interesting aspects on how to work with data sets in Postgres. First of all, we'll take look at using for performing bulk operations on a larger number of values. Second, we'll take a look at and how to generate sample data if you do not have large amounts of input data. Last, but not least, we'll take a look at a PostGIS community example, where somebody had a particular challenge, indexing PostGIS data, and we'll take a look at how a PostGIS core team member…
Continue reading5mins of Postgres E1: Using Postgres statistics to improve bad query plans, pg_hint_plan extension
20 January, 2022Hello, and welcome to 5 minutes of Postgres! Today, we are starting a new weekly video series where we'll walk through interesting articles about Postgres from the last week, as well as evergreen blog posts from the past, and provide context and our personal perspective on it. We are planning to publish a new episode of this series every Thursday, so keep an eye out! We'll always embed the video first, but below it you can find a transcription in case you want to read through what we discussed…
Continue readingPostgres in 2021: An Observer's Year In Review
07 January, 2022Every January, the pganalyze team takes time to sit down to reflect on the year gone by. Of course, we are thinking about pganalyze, our customers and how we can improve our product. But, more importantly, we always take a bird's-eye view at what has happened in our industry, and specifically in the Postgres community. As you can imagine: A lot! So we thought: Instead of trying to summarize everything, let's review what happened with the Postgres project, and what is most exciting from our…
Continue readingThe Fastest Way To Load Data Into Postgres With Ruby on Rails
14 December, 2021Data migration is a delicate and sometimes complicated and time-consuming process. Whether you are loading data from a legacy application to a new application or you just want to move data from one database to another, you’ll most likely need to create a migration script that will be accurate, efficient, and fast to help with the process — especially if you are planning to load a huge amount of data. There are several ways you can load data from an old Rails app or other application to Rails. In…
Continue readingUnderstanding Postgres GIN Indexes: The Good and the Bad
02 December, 2021Adding, tuning and removing indexes is an essential part of maintaining an application that uses a database. Oftentimes, our applications rely on sophisticated database features and data types, such as JSONB, array types or full text search in Postgres. A simple B-tree index does not work in such situations, for example to index a JSONB column. Instead, we need to look beyond, to GIN indexes. Almost 15 years ago to the dot, GIN indexes were added in Postgres 8.2, and they have since become an…
Continue readingUsing PostgreSQL Views in Django
16 November, 2021At my first job, we worked with a lot of data. I quickly found that when there's a lot of data, there are bound to be some long, convoluted SQL queries. Many of ours contained multiple joins, conditionals, and filters. One of the ways we kept the complexity manageable was to create views for common queries. Views in PostgreSQL allow you to query against the results of another query. Views can be composed of columns from one or more tables or even other views, and they are easy to work with in a…
Continue readingHow we deconstructed the Postgres planner to find indexing opportunities
02 November, 2021Everyone who has used Postgres has directly or indirectly used the Postgres planner. The Postgres planner is central to determining how a query gets executed, whether indexes get used, how tables are joined, and more. When Postgres asks itself "How do we run this query?”, the planner answers. And just like Postgres has evolved over decades, the planner has not stood still either. It can sometimes be challenging to understand what exactly the Postgres planner does, and which data it bases its…
Continue readingA better way to index your Postgres database: pganalyze Index Advisor
23 September, 2021When you run an application with a relational database attached, you will no doubt have encountered this question: Which indexes should I create? For some of us, indexing comes naturally, and B-tree, GIN and GIST are words of everyday use. And for some of us it’s more challenging to find out which index to create, taking a lot of time to get right. But what unites us is that creating and tweaking indexes is part of our job when we use a relational database such as Postgres in production. We need…
Continue readingUsing Postgres CREATE INDEX: Understanding operator classes, index types & more
12 August, 2021Most developers working with databases know the challenge: New code gets deployed to production, and suddenly the application is slow. We investigate, look at our APM tools and our database monitoring, and we find out that the new code caused a new query to be issued. We investigate further, and discover the query is not able to use an index. But what makes an index usable by a query, and how can we add the right index in Postgres? In this post we’ll look at the practical aspects of using the…
Continue readingEfficient Pagination in Django and Postgres
20 July, 2021You could say most web frameworks take a naive approach to pagination. Using PostgreSQL’s COUNT, LIMIT, and OFFSET features works fine for the majority of web applications, but if you have tables with a million records or more, performance degrades quickly. Django is an excellent framework for building web applications, but its default pagination method falls into this trap at scale. In this article, I’ll help you understand Django’s pagination limitations and offer three alternative methods…
Continue readingPostgreSQL Partitioning in Django
08 July, 2021Postgres 10 introduced partitioning to improve performance for very large database tables. You will typically start to see the performance benefits with tables of 1 million or more records, but the technical complexity usually doesn’t pay off unless you’re dealing with hundreds of gigabytes of data. Though there are several advantages to partitioning, it requires more tables, which can become cumbersome to work with, especially if you change your data structure in the future. Please note: If you…
Continue readingUsing GeoDjango and PostGIS in Django
24 June, 2021Spatial data is any geographic data that contains information related to the earth, such as rivers, boundaries, cities, or natural landmarks. It describes the contours, topology, size, and shape of these features. Maps are a common method of visualizing spatial data, which is typically represented in vector or raster form. In this article, I’ll introduce you to spatial data in PostgreSQL and Django. You’ll see how to use PostGIS and GeoDjango to create, store, and manipulate geographic data…
Continue readingUsing Postgres Row-Level Security in Ruby on Rails
25 May, 2021Securing access to your Postgres database is more important than ever. With applications growing more complex, often times using multiple programming languages and frameworks within the same app, it can be challenging to ensure access to customer data is handled consistently. For example, if you are building a SaaS application where different companies use the application, you don't want users of Company A to see the data of users in Company B by accident. Sure, you could use create a separate…
Continue readingAn early look at Postgres 14: Performance and Monitoring Improvements
21 May, 2021The first beta release of the upcoming Postgres 14 release was made available yesterday. In this article we'll take a first look at what's in the beta, with an emphasis on one major performance improvement, as well as three monitoring improvements that caught our attention. Before we get started, I wanted to highlight what always strikes me as an important unique aspect of Postgres: Compared to most other open-source database systems, Postgres is not the project of a single company, but rather…
Continue readingCreating Custom Postgres Data Types in Rails
22 April, 2021Postgres ships with the most widely used common data types, like integers and text, built in, but it's also flexible enough to allow you to define your own data types if your project demands it. Say you're saving price data and you want to ensure that it’s never negative. You might create a type that you could then use to define columns on multiple tables. Or maybe you have data that makes more sense grouped together, like GPS coordinates. Postgres allows you to create a type to hold that data…
Continue readingIntroducing pg_query 2.0: The easiest way to parse Postgres queries
18 March, 2021The query parser is a core component of Postgres: the database needs to understand what data you're asking for in order to return the right results. But this functionality is also useful for all sorts of other tools that work with Postgres queries. A few years ago, we released pg_query to support this functionality in a standalone C library. pganalyze uses pg_query to parse and analyze every SQL query that runs on your Postgres database. Our initial motivation was to create pg_query for checking…
Continue readingEfficient Postgres Full Text Search in Django
24 February, 2021In this article, we'll take a look at making use of the built-in, natural language based Postgres Full Text Search in Django. Internet users have gotten increasingly discerning when it comes to search. When they type a keyword into your website's search bar, they expect to find logically ranked results, including related matches and misspellings. Because users are used to these sophisticated search systems, developers have to build applications that use more than simple queries. Postgres Full…
Continue readingCreating Custom Postgres Data Types in Django
15 December, 2020Postgres allows you to define custom data types when the default types provided don't fit your needs. There are many situations where these custom data types come in handy. For example, if you have multiple columns in several tables that should be an between 0 and 255, you could use a custom data type so that you only have to define the constraints once. Or, if you have complex data - like metadata about a file - and you want to save it to a single column instead of spreading it across several…
Continue readingPostGIS vs. Geocoder in Rails
01 October, 2020This article sets out to compare PostGIS in Rails with Geocoder and to highlight a couple of the areas where you'll want to (or need to) reach for one over the other. I will also present some of the terminology and libraries that I found along the way of working on this project and article as I set out to understand PostGIS better and how it is integrated with Rails. If you are interested in learning how to work with geospatial data with PostGIS in Django I recommend having a look at our blog…
Continue readingLessons Learned from Running Postgres 13: Better Performance, Monitoring & More
21 September, 2020Postgres 13 is almost here. It's been in beta since May, and the general availability release is coming any day. We've been following Postgres 13 closely here at pganalyze, and have been running the beta in one of our staging environments for several months now. There are no big new features in Postgres 13, but there are a lot of small but important incremental improvements. Let's take a look. Performance Smaller Indexes with B-Tree Deduplication Extended Statistics Improvements in Postgres 1…
Continue readingUsing Postgres Row-Level Security in Python and Django
13 August, 2020Postgres introduced row-level security in 2016 to give database administrators a way to limit the rows a user can access, adding an extra layer of data protection. What's nice about RLS is that if a user tries to select or alter a row they don't have access to, their query will return 0 rows, rather than throwing a permissions error. This way, a user can use , and they will only receive the rows they have access to with no knowledge of rows they don't. Most examples of RLS limit row access by…
Continue readingUsing Postgres JSONB Fields in Django
30 July, 2020I remember the first time I built user preferences into an app. At first, users just needed to be able to opt in or out of our weekly emails. "No big deal," I thought, "I'll just add a new field on the Users table." For a while, that was fine. A few weeks later, my boss asked me if we could let users opt into push notifications. Fine, that's just one more column on the database. Can't hurt, right? You probably see where this is going. Within months, my user table had 40 columns, and while…
Continue readingBuilding SVG Components in React
09 July, 2020React is well known as a great tool for building complex applications from HTML and CSS, but that same approach can also be used with SVG to build sophisticated custom UI elements. In this article, we'll give a brief overview of SVG, when to use it (and when not to), and how to use it effectively in a React application. We'll also briefly touch on how to integrate with d3 (which comes in very useful when working with SVG). We relied heavily on SVG to build the charting updates we launched…
Continue readingAdvanced Active Record: Using Subqueries in Rails
24 June, 2020Active Record provides a great balance between the ability to perform simple queries simply, and also the ability to access the raw SQL sometimes required to get our jobs done. In this article, we will see a number of real-life examples of business needs that may arise at our jobs. They will come in the form of a request for data from someone else at the company, where we will first translate the request into SQL, and then into the Rails code necessary to find those records. We will be covering…
Continue readingIntroducing New Charts & Date Picker in pganalyze
29 April, 2020Clear and flexible presentation of data is the bread and butter of a monitoring service. A good one will display the right data, but a great one can guide you toward meaningful insights. Visual representation of data in a clear and concise way can help you make decisions quickly. Today we're releasing multiple updates to pganalyze that will help you get to insights more effectively, and keep your database running smoothly. Date range selection as a first-class concept Consistent charts across…
Continue readingFull Text Search in Milliseconds with Rails and PostgreSQL
16 April, 2020Imagine the following scenario: You have a database full of job titles and descriptions, and you’re trying to find the best match. Typically you’d start by using an ILIKE expression, but this requires the search phrase to be an exact match. Then you might use trigrams, allowing spelling mistakes and inexact matches based on word similarity, but this makes it difficult to search using multiple words. What you really want to use is Full Text Search, providing the benefits of ILIKE and trigrams…
Continue readingEffectively Using Materialized Views in Ruby on Rails
16 January, 2020It's every developer's nightmare: SQL queries that get large and unwieldy. This can happen fairly quickly with the addition of multiple joins, a subquery and some complicated filtering logic. I have personally seen queries grow to nearly one hundred lines long in both the financial services and health industries. Luckily Postgres provides two ways to encapsulate large queries: Views and Materialized Views. In this article, we will cover in detail how to utilize both views and materialized views…
Continue readingIntroducing Automated Postgres EXPLAIN Visualization & Insights
16 December, 2019Today, we’re excited to introduce you to the next evolution of pganalyze. We updated our logo and overall brand, worked on our documentation to help you understand Postgres and its internals better and, most importantly, we’re proud to announce a new key feature on our platform: Automated EXPLAIN Visualization & Insights. Automatic Collection of Query Plans Automatic Visualization of Postgres EXPLAIN Plans pganalyze EXPLAIN Insights The new pganalyze brand Offering this functionality to you is a…
Continue readingSimilarity in Postgres and Rails using Trigrams
19 November, 2019You typed "postgras", did you mean "postgres"? Use the best tool for the job. It seems like solid advice, but there's something to say about keeping things simple. There is a training and maintenance cost that comes with supporting an ever growing number of tools. It may be better advice to use an existing tool that works well, although not perfect, until it hurts. It all depends on your specific case. Postgres is an amazing relational database, and it supports more features than you might…
Continue readingEfficient GraphQL queries in Ruby on Rails & Postgres
24 September, 2019GraphQL puts the user in control of their own destiny. Yes, they are confined to your schema, but beyond that they can access the data in any which way. Will they ask only for the "events", or also for the "category" of each event? We don't really know! In REST based APIs we know ahead of time what will be rendered, and can plan ahead by generating the required data efficiently, often by eager-loading the data we know we'll need. In this article, we will discuss what N+1 queries are, how they…
Continue readingPostgres Connection Tracing, Wait Event Analysis & Vacuum Monitoring go into GA on pganalyze
14 April, 2019We’re excited to announce the general availability of three new pganalyze features: Connection Tracing, Wait Event Analysis, as well as Vacuum Monitoring. These features have been developed based on the feedback of hundreds of customers monitoring their production Postgres databases using pganalyze. Thanks so much for consistently taking the time to provide us with valuable information on how you’d like to see pganalyze evolve! Postgres Connection Tracing & Wait Event Analysis One of the most…
Continue readingNew in Postgres 11: Monitoring JIT performance, Auto Prewarm & Stored Procedures
04 October, 2018Everyone’s favorite database, PostgreSQL, has a new release coming out soon: Postgres 11 In this post we take a look at some of the new features that are part of the release, and in particular review the things you may need to monitor, or can utilize to increase your application and query performance. Just-In-Time compilation (JIT) in Postgres 11 Just-In-Time compilation (JIT) for query execution was added in Postgres 11. It's not going to be enabled for queries by default, similar to parallel…
Continue readingPostgres Log Monitoring with pganalyze: Introducing Log Insights 2.0
24 July, 2018TLDR: We recently released substantial improvements to our Log Insights feature, including up to 30 day history, support for Heroku Postgres, as well as support for monitoring the log files of PostgreSQL servers running on-premise. How pganalyze parses Postgres log files Its now been a bit over a year since we first released the log monitoring functionality in pganalyze, and we would like to share a major update with you today. Before diving in, a quick review how the pganalyze collector works…
Continue readingPostgres Log Monitoring 101: Deadlocks, Checkpoint Tuning & Blocked Queries
12 February, 2018Those of us who operate production PostgreSQL databases have many jobs to do - and often there isn't enough time to take a regular look at the Postgres log files. However, often times those logs contain critical details on how new application code is affecting the database due to locking issues, or how certain configuration parameters cause the database to produce I/O spikes. This post highlights three common performance problems you can find by looking at, and automatically filtering your…
Continue readingVisualizing & Tuning Postgres Autovacuum
28 November, 2017In this post we'll take a deep dive into one of the mysteries of PostgreSQL: VACUUM and autovacuum. The Postgres autovacuum logic can be tricky to understand and tune - it has many moving parts, and is hard to understand, in particular for application developers who don't spend all day looking at database documentation. But luckily there are recent improvements in Postgres, in particular the addition of pg_stat_progress_vacuum in Postgres 9.6, that make understanding autovacuum and VACUUM…
Continue readingWhats New in Postgres 10: Monitoring Improvements
04 October, 2017Postgres 10 has been stamped on Monday, and will most likely be released this week, so this seems like a good time to review what this new release brings in terms of Monitoring functionality built into the database. In this post you'll see a few things that we find exciting about the new release, as well as some tips on what to adjust, whether you use a hosted Postgres monitoring tool like pganalyze, or if you've written your own scripts. New "pg_monitor" Monitoring Role Most users of Postgres…
Continue readingIntroducing Log Insights: Realtime Analysis of Postgres Logs
07 June, 2017After significant development effort, we're excited to introduce you to a new part of pganalyze that we believe every production Postgres database needs: pganalyze Log Insights UPDATE: We released pganalyze Log Insights 2.0 - read more about it in our article: Postgres Log Monitoring with pganalyze: Introducing Log Insights. In the past you used generic log management systems and setup your own filtering and altering rules, which required a lot of manual effort, as well as knowledge of all…
Continue readingMonitoring PostgreSQL 9.5 & Improved Weekly Reports
06 July, 2015Last week the first official alpha version of PostgreSQL 9.5 was released. Whilst the stable release is still 2-3 months away, now is a good time to review what is upcoming, and which changes and improvements we can expect. Here is an overview of the most important changes for monitoring tools: pg_stat_statements gets new columns min_time, max_time, mean_time & stddev_time - making it much easier to identify outliers in the query statistics New pg_stat_ssl view that shows active SSL connections…
Continue readingIntroducing pg_query: Parse PostgreSQL queries in Ruby
17 June, 2014In this article we'll take a look at the new pg_query Ruby library. pg_query is a Ruby library I wrote to help you parse SQL queries and work with the PostgreSQL parse tree. We use this extension inside pganalyze to provide contextual information for each query and find columns which might need an index. At the end of this article you'll also find monitor.rb - a ready-to-use example that filters pg_stat_statements output and restricts it to only show a specific table. Existing Solutions to Parse…
Continue readingAnnouncing The All-New Database Check-Up
20 March, 2014We’ve just launched our new version of Database Check-Up - allowing you to see more quickly what could be relevant to look at in your database. In addition we’ve also revamped the detail pages of queries, tables, indices and config settings to match the new style: Improved Check-Up: Config Settings When working with other people's PostgreSQL databases, we’ve seen a lot of things, from fsync=off (which you really only want if you don’t care about your data or have no writes) to simple…
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