Table descriptor
The table descriptor, or MI_AM_TABLE_DESC structure, provides information about the index, particularly the data definition from the CREATE INDEX statement that created the object.
The following accessor functions extract information from
or set values in the table descriptor.
| Accessor function | Return value |
|---|---|
| mi_tab_amparam() | Parameter values from the USING clause of the CREATE INDEX statement |
| mi_tab_check_is_recheck() | MI_TRUE if the database server calls am_check to recheck and possibly repair an index |
| mi_tab_createdate() | The date that the index was created |
| mi_tab_isindex() | MI_TRUE for a secondary access method |
| mi_tab_isolevel() | The isolation level |
| mi_tab_keydesc() | A pointer to the key descriptor |
| mi_tab_mode() | The input/output mode (read-only, read and write, write-only, and log transactions) |
| mi_tab_name() | The index name |
| mi_tab_nextrow() | One entry from shared memory to insert in a new index |
| mi_tab_niorows() | The number of rows that mi_tab_setniorows() sets |
| mi_tab_nparam_exist() | The number of indexes that are defined for the same combination of table key columns |
| mi_tab_numfrags() | The number of fragments in the index or 1 for a nonfragmented index |
| mi_tab_owner() | The index owner |
| mi_tab_param_exist() | Configuration parameters and values for one of multiple indexes that pertain to the same table and composite key |
| mi_tab_partnum() | The unique partition number, or fragment identifier, of this index or fragment |
| mi_tab_rowdesc() | A pointer to a row descriptor that describes the columns in the composite index key |
| mi_tab_spaceloc() | The extspace location of the index fragment |
| mi_tab_spacename() | The storage space name for the fragment from the CREATE INDEX statement IN clause |
| mi_tab_spacetype() | The type of space used for the index: X for
an extspace or S for an sbspace Any other value means
that neither an IN clause nor the sysams system catalog table
specifies the type of storage space. |
| mi_tab_unique() | MI_TRUE if this index should enforce unique keys |
| mi_tab_update_stat_mode() | The level of statistics that an UPDATE STATISTICS statement generates: low, medium, or high |
| mi_tab_userdata() | A pointer to the user-data area of memory |
The following accessor functions set values in the table
descriptor.
| Accessor function | Value set |
|---|---|
| mi_tab_check_set_ask() | An indicator that am_check detects a problem in an index |
| mi_tab_setniorows() | The number of rows that shared memory can store from a scan for a new index |
| mi_tab_setnextrow() | One row of the number that mi_tab_setniorows() allows |
| mi_tab_setuserdata() | A pointer in the user-data area of memory |