Pseudo codestructure naar Mysql?

Kan iemand helpen om de volgende pseudocode in mysql? De resulterende selecteert in de IF statement alle keren dezelfde kolommen (4) en meerdere rijen (onbekend), dus dat is niet echt het probleem dat ik ben geconfronteerd .. Hoe kan ik de volgende structuur in Mysql?

//parameters
@p1;
@p2;

@v1;
@v2;

//vars
@t1= 15000;
@t2 = 15000;

//calculated vars
@overlap1 = (@p1 + @v1) > @t1; //boolean
@overlap2 = (@p2 + @v2) > @t2; //boolean
@overlap = @overlap1 OR @overlap2; //boolean


If NOT @overlap Then //no overlap
    CUSTOM SELECT QUERIES (UNION etc..)
ElseIf @overlap1 AND @overlap2 //both overlaps true
    CUSTOM SELECT QUERIES (UNION etc..)
ElseIf @overlap1 //only @overlap1
    CUSTOM SELECT QUERIES (UNION etc..)
Else //only @overlap2
    CUSTOM SELECT QUERIES (UNION etc..)
End If