TMMUpdateMode

Declared in: EDBMMClient

TMMUpdateMode = (
  umInsert,  // plain INSERT INTO ... VALUES (...)
  umUpdate,  // UPDATE ... SET ... WHERE <Where expression>
  umUpsert   // INSERT ... ON DUPLICATE KEY UPDATE (idempotent)
);

Write mode assigned to TMMUpdater.Mode before calling Prepare.
Determines the SQL statement the server generates for each batch chunk.

Values

### umInsert

Plain INSERT INTO ... VALUES (...).
Fails if a row with the same primary key already exists.

### umUpdate

UPDATE ... SET ... WHERE ....
Primary key columns are automatically routed to the WHERE clause by the server; all non-PK columns go to SET.
Where is an optional extra AND condition appended to the PK predicate.
Rows not matched are silently skipped (no error).

### umUpsert

INSERT ... ON DUPLICATE KEY UPDATE ....
Inserts the row when the primary key is absent; updates the non-key columns when it already exists.
Idempotent — safe to repeat on the same data.

See Also

• Types
• TMMUpdater