PostgreSQL SyntaxLesson 19Free preview

PostgreSQL WHERE

This lesson is part of PostgreSQL · All levels

Summary

The WHERE clause filters the line so that only those who meet certain conditions are included in the processing or display. In it you can use the comparison operator, combining AND and OR, to specific conditions like LIKE, IN, and BETWEEN. Note that the value NULL requires special checking with IS NULL.

Key points

WHERE filter the line according to the condition before the result is presented.
Supports the operators =, <>, >, <, >=, <= as well as the logic AND, OR, NOT.
Special conditions are available via LIKE, IN, BETWEEN, and IS.
The condition against NULL should use IS NULL, not operator =.

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