LIKE Patterns

Percent Contains

Percent on both sides checks for contained text.

highlighted = computed this step

Percent on both sides

Percent on both sides makes a contains-style check.

contains check\text{contains check}

Read contains matches

The contains pattern keeps 2 rows.

TRUE rows=2\text{TRUE rows}=2

LIKE-pattern examples are tiny finite WHERE-style filters with a small SQL-like pattern subset; collations, escapes, dialect behavior, indexes, optimizer behavior, and product claims are out of scope.

Percent on both sides: base rowsidname1Ada2Al3Alan4Bea5Jo6NULL LIKE evaluationsourcevaluepatterntruthkept0Ada%l%FALSEno1Al%l%TRUEyes2Alan%l%TRUEyes3Bea%l%FALSEno4Jo%l%FALSEno5NULL%l%UNKNOWNno LIKE output rowsidname2Al3Alan LIKE factsfactvalueinputRowCount6outputRowCount2trueRows2falseRows3unknownRows1patternKindpercentrowOrdersource_order

Middle can vary

The required letter can appear after any prefix and before any suffix.

any sides around it\text{any sides around it}

Summary

A contains pattern is still exact about the required middle text.

required middle\text{required middle}