I have a DB2 Server and I want to select data depending on the condition. If I have the Value Value in the ColumnX, ColumnY or ColumnZ it should search for it between the TB2.Column1 and TB3.Column1 My statement is a bunch of left outer joins but it looks like that:

SELECT
CASE
    WHEN (TB1.ColumnX || TB1.ColumnY || TB1.ColumnZ) = 'Value'
    THEN Statement1
    ELSE ' '
END AS MyColumn
FROM
TB1 LEFT OUTER JOIN TB2 ON TB1.JOINCOL = TB2.JOINCOL
    LEFT OUTER JOIN TB3 ON TB2.JOINCOL2 = TB3.JOINCOL
WHERE TB1.Column1 between TB2.Column1 and TB3.Column1

But it doesn't work, is there a mistake in the syntax?