SAP FROM WA documentation, setup help and usage info

INCLUDE
What does it do? For wa , a work area compatible to the row type of the internal table must be specified. This concerns functional operand positions . The first row of the internal table found, whose values in the columns of the table key used match those of the corresponding components of wa
, is processed. If the key fields in wa are empty, no entries are processed.
If the USING KEY addition is not specified, the primary table key is used. If the USING KEY addition is specified, the table key specified in keyname is used.

SAP FROM WA documentation, setup help and example usage