Why does NoConcatenate create a synthetic key ?

[#1]

Hello,

In my simple QVW script I have two identical Excel sheets (the number of columns and the column names are the same) which I am loading into two tables - Table A and Table B.

I prefix my load of Table B with the NOCONCATENATE statement so the rows will load into their respective tables, which they do.

TableA:

LOAD *

FROM Data\Test.xlsx (ooxml, embedded labels, table is [Sheet A]);

NoConcatenate

TableB:

LOAD *

FROM Data\Test.xlsx (ooxml, embedded labels, table is [Sheet B]);

Can someone please explain why this generates a synthetic key ? I thought the NoConcatenate  statement prevented this.

Thanks

MV

[ecolomer · Accepted solution]

If you have the same field names, QV create an relation and synthetic keys.

For separate name use QUALIFY

QUALIFY *;

TableA:

LOAD *

FROM Data\Test.xlsx (ooxml, embedded labels, table is [Sheet A]);

NoConcatenate

TableB:

LOAD *

FROM Data\Test.xlsx (ooxml, embedded labels, table is [Sheet B]);

[ecolomer]

See this:

Do you Qualify?- How to use QUALIFY statement

[sarvesh]

Syntax of Nonconcatenate is mentioned below please check:

LOAD a, b, c from table1.csv;

noconcatenate LOAD a, b, c from table2.csv;

Regard's

sarvesh Srivasrava

[#5]

Thank you Enrique for the solution and the explanation.

MV

[#6]

Yes, that's what I had Sarvesh.

[jwaligora]

Hi. I realize this is an ancient thread, but on the off chance you're still around...

When Qualify * is used, the behaviour appears to be the same regardless of whether or not NoConcatenate is also applied.  What are use cases in which NoConcatenate would actually make a difference?