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SQL Anywhere cursors are classified by their sensitivity with respect to changes of the underlying data. In particular, cursor sensitivity is defined in terms of which changes are visible.
Insensitive cursors The result set is fixed when the cursor is opened. No changes to the underlying data are visible. See Insensitive cursors.
Sensitive cursors The result set can change after the cursor is opened. All changes to the underlying data are visible. See Sensitive cursors.
Asensitive cursors Changes may be reflected in the membership, order, or values of the result set seen through the cursor, or may not be reflected at all. See Asensitive cursors.
Value-sensitive cursors Changes to the order or values of the underlying data are visible. The membership of the result set is fixed when the cursor is opened. See Value-sensitive cursors.
The differing requirements on cursors place different constraints on execution, and so, performance. For more information, see Cursor sensitivity and performance.