Hi,
NULL doesn't exist with Sage X3. Table columns are always populated with blanks or 0s.

If you want to have NULL and you manage that out of 4GL, you can simply do a FOR .. SQL loop that will execute the query you give it in parameter.

Extract from X3 Online help:

  # Example 1: Request to select a maximum value in a table
  Local Char REQUEST(255)
  Local Integer MAX_VAL
  REQUEST="select max(ACCNUM_0) From GACCENTRYD"
  For (Integer NUM) From "3" Sql REQUEST As [XXX]
    MAX_VAL=[F:XXX]NUM
  Next

From "3"= Oracle
From "5" or From "S" = SQL Server

You can also use a clob field instead of a char variable to store the query.

Hello Bruno Bruno Gonzalez 

Thank you very much for your fast help. Highly appreciated.

Yes X3 don't know null. Normally I knew this Because storing the query in a clob was a bigger modification in the code I was watching for an alternative. Then I saw this post https://www.sagecity.com/us/sage_x3/f/general-discussion/101401/4gl-how-to-outer-join which made me unsure and  I thought AVOID.AINT maybe converts in the resulting sql query to NULL. But AVOID represents the empty value for the corresponding data type. In case of AVOID.AINT this is the 0 value.

So finally I stored, as you suggested, the query in a clob.

Like this it works as intended.

Thank you again.

Best regards