MI_ISOLATION_LEVEL mi_scan_isolevel(MI_AM_SCAN_DESC *scanDesc);

scanDesc

points to the scan descriptor.

If the access method supports isolation levels, it can call mi_scan_isolevel() from am_beginscan to determine the appropriate isolation level. For a detailed description of isolation levels, see Checking Isolation Levels.

Call mi_scan_isolevel() to validate that the isolation level requested by the application does not surpass the isolation level that the access method supports. If the access method supports Serializable, it does not call mi_scan_isolevel() because Serializable includes the capabilities of all the other levels.

MI_ISO_NOTRANSACTION indicates that no transaction is in progress.

MI_ISO_READUNCOMMITTED indicates Dirty Read.

MI_ISO_READCOMMITTED indicates Read Committed.

MI_ISO_CURSORSTABILITY indicates Cursor Stability.

MI_ISO_REPEATABLEREAD indicates Repeatable Read.

MI_ISO_SERIALIZABLE indicates Serializable.

See the descriptions of:

• Functions mi_scan_locktype() and mi_tab_isolevel()
• Isolation levels in Checking Isolation Levels
• Sample isolation-level language for access-method documentation (Figure 14)