Overview¶
To process SQL statements, the stored procedure process assigns a memory segment to store context association. Cursors are handles or pointers to context areas. With cursors, stored procedures can control alterations in context areas.
Important
If JDBC is used to call a stored procedure whose returned value is a cursor, the returned cursor is not available.
Cursors are classified into explicit cursors and implicit cursors. Table 1 shows the usage conditions of explicit and implicit cursors for different SQL statements.
SQL Statement | Cursor |
|---|---|
Non-query statements | Implicit |
Query statements with single-line results | Implicit or explicit |
Query statements with multi-line results | Explicit |