Can I use… case when … (searched)

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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'
  FROM …

Normative References

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

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