I have tables and views a, b, c, d waiting for a query.
b needs using inner join with a,
c needs using exists join with a,
d needs using exists join with a.
So how should i put them in a query code? I am currently putting inner join first and exist join later but the query crashes when it reaches first exist join. Please help.
Like :
if(condition B stands )
{
qdbsB = qbdsA.addDataSource(B);
qdbsB .addLink(fieldNum(A,field A),fieldNum(B,field B));
qdbsB .joinMode(JoinMode::InnerJoin);
Range B
}
if(condition C stands )
{
qdbsC = qbdsA.addDataSource(C);
qdbsC .addLink(fieldNum(A, field A),fieldNum(C,field C));
qdbsC .joinMode(JoinMode::ExistsJoin);
Range C
}
if(condition D stands )
{
qdbsD = qbdsA.addDataSource(D);
qdbsD .addLink(fieldNum(A,field A),fieldNum(D,field D));
qdbsD .joinMode(JoinMode::ExistsJoin);
Range D
}