Magic xpa SQL Where and DB SQL Where Behavior (Magic xpa 4.x)
When a data view is created for a task, Magic xpa generates a SELECT statement with a Where clause.
The first part of the WHERE clause is based on the From and To expressions of the columns in the data view. The second part of the WHERE clause is the link Inner Join/Left Outer Join condition. The third part is the Magic xpa SQL Where, which is added to every SELECT statement. The fourth part is the DB SQL Where, which is added to every SELECT statement.
The column’s values are evaluated only once when entering the task, and no recomputing is done. The only time that the SQL Where is not used, is when Magic xpa generates SELECT statements for the internal Get Current and Hook (determined by the locking strategy) operations. In these operations, Magic xpa uses the position index to get the row, and the SQL Where is not needed.
Strings created by the Magic xpa SQL Where clause are sent from the expression evaluator to the gateway in Unicode format. If a gateway does not support Unicode strings for statements, the gateway converts the string into ANSI format using the default code page.
Magic xpa SQL Where and DB SQL Where Usage Considerations
Magic xpa SQL Functions
