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SQLSetScrollOptions Mapping

  • مقالة

When an application calls SQLSetScrollOptions through an ODBC 3.x driver and the driver does not support SQLSetScrollOptions, the call to

SQLSetScrollOptions(StatementHandle, Concurrency, KeysetSize, RowsetSize)

will result as follows:

  • A call to

    SQLGetInfo(ConnectionHandle, InfoType, InfoValuePtr, BufferLength, StringLengthPtr)

    with the InfoType argument set to one of the values in the following table, depending on the value of the KeysetSize argument in SQLSetScrollOptions.

    KeysetSize argument InfoType argument
    SQL_SCROLL_FORWARD_ONLY SQL_FORWARD_ONLY_CURSOR_ATTRIBUTES2
    SQL_SCROLL_STATIC SQL_STATIC_CURSOR_ATTRIBUTES2
    SQL_SCROLL_KEYSET_DRIVEN SQL_KEYSET_CURSOR_ATTRIBUTES2
    SQL_SCROLL_DYNAMIC SQL_DYNAMIC_CURSOR_ATTRIBUTES2
    A value greater than the RowsetSize argument SQL_KEYSET_CURSOR_ATTRIBUTES2

    If the value of the KeysetSize argument is not listed in the preceding table, the call to SQLSetScrollOptions returns SQLSTATE S1107 (Row value out of range) and none of the following steps are performed.

    The Driver Manager then verifies whether the appropriate bit is set in the *InfoValuePtr value returned by the call to SQLGetInfo, according to the value of the Concurrency argument in SQLSetScrollOptions.

    Concurrency argument InfoType setting
    SQL_CONCUR_READ_ONLY SQL_CA2_READ_ONLY_CONCURRENCY
    SQL_CONCUR_LOCK SQL_CA2_LOCK_CONCURRENCY
    SQL_CONCUR_ROWVER SQL_CA2_ROWVER_CONCURRENCY
    SQL_CONCUR_VALUES SQL_CA2_VALUES_CONCURRENCY

    If the Concurrency argument is not one of the values in the preceding table, the call to SQLSetScrollOptions returns SQLSTATE S1108 (Concurrency option out of range) and none of the following steps are performed. If the appropriate bit (as indicated in the preceding table) is not set in *InfoValuePtr to one of the values corresponding to the Concurrency argument, the call to SQLSetScrollOptions returns SQLSTATE S1C00 (Driver not capable) and none of the following steps are performed.

  • A call to

    SQLSetStmtAttr(StatementHandle, SQL_ATTR_CURSOR_TYPE, ValuePtr, 0)

    with *ValuePtr set to one of the values in the following table, according to the value of the KeysetSize argument in SQLSetScrollOptions.

    KeysetSize argument *ValuePtr
    SQL_SCROLL_FORWARD_ONLY SQL_CURSOR_FORWARD_ONLY
    SQL_SCROLL_STATIC SQL_CURSOR_STATIC
    SQL_SCROLL_KEYSET_DRIVEN SQL_CURSOR_KEYSET_DRIVEN
    SQL_SCROLL_DYNAMIC SQL_CURSOR_DYNAMIC
    A value greater than the RowsetSize argument SQL_CURSOR_KEYSET_DRIVEN

  • A call to

    SQLSetStmtAttr(StatementHandle, SQL_ATTR_CONCURRENCY, ValuePtr, 0)

    with *ValuePtr set to the Concurrency argument in SQLSetScrollOptions.

  • If the KeysetSize argument in the call to SQLSetScrollOptions is positive, a call to

    SQLSetStmtAttr(StatementHandle, SQL_ATTR_KEYSET_SIZE, ValuePtr, 0)

    with *ValuePtr set to the KeysetSize argument in SQLSetScrollOptions.

  • A call to

    SQLSetStmtAttr(StatementHandle, SQL_ROWSET_SIZE, ValuePtr, 0)

    with *ValuePtr set to the RowsetSize argument in SQLSetScrollOptions.

    Note

    When the Driver Manager maps SQLSetScrollOptions for an application working with an ODBC 3.x driver that does not support SQLSetScrollOptions, the Driver Manager sets the SQL_ROWSET_SIZE statement option, not the SQL_ATTR_ROW_ARRAY_SIZE statement attribute, to the RowsetSize argument in SQLSetScrollOption. As a result, SQLSetScrollOptions cannot be used by an application when fetching multiple rows by a call to SQLFetch or SQLFetchScroll. It can be used only when fetching multiple rows by a call to SQLExtendedFetch.