• Data Warehouse Service

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  2. Data Warehouse Service
  3. Developer Guide
  4. Stored Procedures
  5. Cursors
  6. Overview

Overview

To process SQL statements, the stored procedure process assigns a memory segment to store context association. Cursors are handles or pointers to context regions. With cursors, stored procedures can control alterations in context regions.

If JDBC is used to call a stored procedure whose returned value is a cursor, the returned cursor cannot be used.

Cursors are classified into explicit cursors and implicit cursors. Table 1 shows the usage conditions of explicit and implicit cursors for different SQL statements.

Table 1 Cursor usage conditions

SQL Statement

Cursor

Non-query statements

Implicit

Query statements with single-line results

Implicit or explicit

Query statements with multi-line results

Explicit