Can I use… case when … (searched)


Apache DerbyBigQueryDb2 (LUW)H2MariaDBMySQLOracle DBPostgreSQLSQL ServerSQLite200520072009201120132015201720192021✓ 3.5.7+✓ 2008R2+✓ 8.3+✓ 11gR1+✓ 5.0+✓ 5.1+✓ 1.4.191+✓ 9.7+✓ 2.0+✓ 10.15.1.3+

Case is a conditional SQL expression: It returns the value of that then expression which follows the first true when clause. If no when condition is true, the value of the else expression is returned or null if there is no else.

SELECT CASE WHEN x > 100 THEN 'too large'
                         ELSE 'ok'
             END
  FROM …

Normative References

The searched case expression is defined in ISO/IEC 9075:2016-2 as mandatory feature F261-02.

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