How Do I Use Boolean Values in SQL SELECT Statements?

Querying with BOOLEAN Values in SELECT Statements

Your question revolves around leveraging a database function containing a BOOLEAN parameter within a SELECT statement. However, directly utilizing the TRUE keyword results in an "invalid identifier" error.

Understanding SQL's Limitations

While your expectation of using TRUE/FALSE as BOOLEAN values seems reasonable, SQL limitations do not allow direct representation of BOOLEAN data types.

Workaround: Representing TRUE/FALSE as Integer or String

To resolve this issue, SQL provides two workarounds:

1. Using Numeric Representation (1/0): Assign 1 to represent TRUE and 0 for FALSE. This method enables the use of Boolean values within numerical calculations.

   CASE WHEN (10 > 0) THEN 1 ELSE 0 END AS MY_BOOLEAN_COLUMN

2. Using String Representation (true/false): Alternatively, you can convert BOOLEAN values to strings. Assign 'true' for TRUE and 'false' for FALSE. This allows for readable and printable Boolean representations.

   SELECT CASE WHEN (10 > 0) THEN 'true' ELSE 'false' END AS MY_BOOLEAN_COLUMN

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