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Items tagged postgresql, mysql

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Announcing DuckDB 0.10.0. Somewhat buried in this announcement: DuckDB has Fixed-Length Arrays now, along with array_cross_product(a1, a2), array_cosine_similarity(a1, a2) and array_inner_product(a1, a2) functions.

This means you can now use DuckDB to find related content (and other tricks) using vector embeddings!

Also notable: “DuckDB can now attach MySQL, Postgres, and SQLite databases in addition to databases stored in its own format. This allows data to be read into DuckDB and moved between these systems in a convenient manner, as attached databases are fully functional, appear just as regular tables, and can be updated in a safe, transactional manner.” # 13th February 2024, 5:57 pm

Generated Columns in SQLite (via) SQLite 3.31.0 released today, and generated columns are the single most notable new feature. PostgreSQL 12 added these in October 2019, and MySQL has had them since 5.7 in October 2015. MySQL and SQLite both offer either “stored” or “virtual” generated columns, with virtual columns being calculated at runtime. PostgreSQL currently only supports stored columns. # 24th January 2020, 4:20 am

db-to-sqlite 1.0 release. I’ve released version 1.0 of my db-to-sqlite tool, which lets you create a SQLite database copy of any database supported by SQLAlchemy (I’ve tested it against MySQL and PostgreSQL). The tool has a bunch of new features: you can use --redact to redact specific columns, specify --table multiple times to copy a subset of tables, and the --all option now efficiently adds all foreign keys at the end of the import. The project now has unit tests which run against MySQL and PostgreSQL in Travis CI. Also included in the README: a shell one-liner for creating a local SQLite copy of a remote Heroku Postgres database based on extracting the connection string from a Heroku config environment variable. # 1st July 2019, 1:35 am

mycli. Really neat auto-complete enabled MySQL terminal client, built using the excellent python-prompt-toolkit. Has a sister-project for PostgreSQL called pgcli. # 11th June 2018, 7:08 pm

Showdown: MySQL 8 vs PostgreSQL 10 (via) MySQL 8 makes comparisons between PostgreSQL and MySQL far more interesting, as it closes some of the key feature gaps. Meanwhile the PostgreSQL replication story (long one of MySQL’s key advantages) has improved dramatically in recent versions. This article offers a useful overview of the current differences, including diving into some of the less obvious implementation details that differ between the two. # 23rd May 2018, 5:02 pm

What tools and techniques are used for relational database version control (structure and data)?

The term you are looking for is database migrations (sometimes called database change scripts).

[... 308 words]

When should one switch from MySQL to Oracle or PostgreSQL?

When your own benchmarks prove that your application’s particular load characteristics will perform better on another database—and the difference is large enough that it’s worth the cost involved in retargeting your code. If that cost is high (and it probably will be) it may be worth paying for some expert consultants to ensure that your implementations against the different databases are properly optimised.

[... 102 words]

Django-Jython 1.0.0 released! Now with database backends for PostgreSQL, Oracle and MySQL. The next release (planned for next month) should provide full compatibility with Django 1.1—the current release has 1.1 support for PostgreSQL but only 1.0 support for the other two databases. # 9th November 2009, 1:53 pm

Django Unit Tests and Transactions. If you’re using a transactional database engine (MySQL with InnoDB, Postgres or SQLite) you can speed things up by running each of your unit tests inside a transaction and rolling back in tearDown(). # 7th July 2008, 2:14 pm

Sun To Acquire MySQL. Sun also employ Josh Berkus, one of the lead developers of PostgreSQL. # 16th January 2008, 1:55 pm