sql

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SQL window functions explained: running totals, rank and LAG in Postgres

GROUP BY collapses your rows and you lose the detail. A window function keeps every row and adds the total, the rank or the previous value beside it. Eight runnable PostgreSQL examples, including the tie trap that makes running totals jump.

Aliteq Team · Oct 16 · 11 min

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Software

Postgres vs MySQL for a new project: pick Postgres unless one of these is true

Both are free and mature. For a new app in 2026, the docs tilt toward Postgres: a permissive licence, indexed jsonb, a free vector extension and hosts on every budget. Here is what each project's own documentation says, what I could not verify, and the cases where MySQL still wins.

Aliteq Team · Oct 16 · 9 min

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Software

Postgres query slow? When to add an index, and when it makes things worse

An index speeds up reads and taxes every write. Here is when it pays, how to order the columns, and how to read EXPLAIN, using the PostgreSQL docs and our own price table, where five indexes take up more room than the data.

Aliteq Team · Oct 9 · 9 min