The mi_tab_mode() accessor function

The mi_tab_mode() function retrieves the I/O mode of the table from the table descriptor.

Syntax

mi_unsigned_integer 
mi_tab_tab_mode(MI_AM_TABLE_DESC *tableDesc)
tableDesc
Points to the table descriptor.

Usage

The I/O mode refers to the operations expected subsequent to the opening of a table.

To determine the input and output requirements of the current statement:

  1. Call mi_tab_mode() to obtain an input/output indicator.
  2. Pass the value that mi_tab_mode() returns to the macros in the following table for interpretation.

    Each macro returns either MI_TRUE or MI_FALSE.

    Table 1. Macro modes
    Macro Mode Verified
    MI_INPUT() Open for input only, usually in the case of a SELECT statement
    MI_OUTPUT() Open for output only, usually in the case of an INSERT statement
    MI_INOUT() Open for input and output, usually in the case of an UPDATE statement
    MI_NOLOG() No logging required
In the following example, the access method calls mi_tab_mode() to verify that a query is read-only. If MI_INOUT() returns MI_FALSE, the access method requests a multiple-row buffer because the access method can return several rows without interruption by an update: 
if (MI_INOUT(tableDesc) == MI_FALSE)
   mi_tab_setniorows(tableDesc, 10);

If MI_INOUT() returns MI_TRUE, the access method can process only one row identifier with each call to am_getnext.

Return values

The integer indicates whether an input or output request is active.

To interpret the returned integer, use the macros that Macro modes describes.