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SQL basics | SQL basics | ||
==Common functions== | ==Common functions== | ||
Latest revision as of 01:43, 12 February 2024
SQL basics
Common functions
Math functions
- Average
- Sum
- Round
Conditional functions
See Postgres conditional functions.
Joins
Joins merge two tables into a single table. You can think of this like an outer product, applying some conditions to subset from every possible combination of rows from the two tables.
- Inner join - creates rows only if keys match between the rows
- Left join - keep all rows from the left table
- Right join - keep all rows from the right table
- Outer join - keep rows from both tables.