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Determining Cursor Capabilities

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The following four options in SQLGetInfo describe what types of cursors are supported and what their capabilities are:

  • SQL_CURSOR_SENSITIVITY. Indicates whether a cursor is sensitive to changes made by another cursor.

  • SQL_SCROLL_OPTIONS. Lists the supported cursor types (forward-only, static, keyset-driven, dynamic, or mixed). All data sources must support forward-only cursors.

  • SQL_DYNAMIC_CURSOR_ATTRIBUTES1, SQL_FORWARD_ONLY_CURSOR_ATTRIBUTES1, SQL_KEYSET_CURSOR_ATTRIBUTES1, or SQL_STATIC_CURSOR_ATTRIBUTES1 (depending on the type of the cursor). Lists the fetch types supported by scrollable cursors. The bits in the return value correspond to the fetch types in SQLFetchScroll.

  • SQL_KEYSET_CURSOR_ATTRIBUTES2 or SQL_STATIC_CURSOR_ATTRIBUTES2 (depending on the type of the cursor). Lists whether static and keyset-driven cursors can detect their own updates, deletes, and inserts.

An application can determine cursor capabilities at run time by calling SQLGetInfo with these options. This is commonly done by generic applications. Cursor capabilities also can be determined during application development and their use hard-coded into the application. This is commonly done by vertical and custom applications but can also be done by generic applications that use a client-side cursor implementation such as the ODBC cursor library.