SQL for Cursor Checkbox
Adaptive Server uses a different query plan for a SQL statement that is embedded in a cursor declaration from the query plan when the SQL statement is not embedded in a cursor. This needs to be taken into account when retrieving the query plan or run time.
Therefore, if the SQL statement comes from or will be embedded in a cursor declaration then you need to select SQL for Cursor in the SQL Editor pane of Index Advisor window. This enables cursor simulation when retrieving the query plan and run time information.
This checkbox is automatically selected in the SQL Editor pane when you use the Send to Index Advisor function from the SQL Scanner if the SQL was extracted from within a cursor declaration.
In Adaptive Server 15 or later, the Declare Cursor Setting window is also available to select specific cursor settings.
View Declare Cursor Settings Window
Cursor Arguments
The cursor arguments should match the settings used for the SQL statement in your application code.
| Item | Description |
|
SEMI-SENSITIVE |
Specify that the worktable which holds the result set is populated only as the rows are fetched. Therefore changes to the data that occur while the cursor is opened may be visible in the result set. |
|
INSENSITIVE |
Specify that the data is copied to a worktable when the cursor is open which makes the data insensitive to changes in the data that may occur while the cursor is opened. |
|
SCROLL |
Specify that the cursor is scrollable meaning that you can position the cursor anywhere in the cursor result set for as long as the cursor is open. All scrollable cursors are read only. |
|
NO SCROLL |
Specify that the rows are retrieved one row at a time. All update cursors are non-scrollable. |