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ABAP - Keyword Documentation → ABAP - Reference → Obsolete Language Elements → Obsolete Processing of External Data → Obsolete Database Access → Obsolete Syntax Forms in Open SQL →Obsolete Host Variables
The host variables of an Open SQL statement can still be specified without the escape character @, unless one of the strict modes of the syntax check from Release 7.40, SP05 is used. This format is obsolete. The escape character @ must always be specified to distinguish ABAP data objects clearly from names in the database.
Example
SELECT statement without escape character in front of named ABAP data objects.
Recommended spelling with escape character in front of named ABAP data objects.