Method updateTable

delta/controller.go:137–190

(
	ctx *sql.Context,
	conn *stdsql.Conn,
	tx *stdsql.Tx,
	table tableIdentifier,
	appender *DeltaAppender,
	stats *FlushStats,
)

}

func (c *DeltaController) updateTable(
	ctx *sql.Context,
	conn *stdsql.Conn,
	tx *stdsql.Tx,
	table tableIdentifier,
	appender *DeltaAppender,
	stats *FlushStats,
) error {
	if tx == nil {
		return fmt.Errorf("no active transaction")
	}
	defer appender.ResetCounters()

	// We consider the following cases:
	//  1. INSERT only - no DELETE or UPDATE. In this case, we can do a simple INSERT INTO in an optimized way,
	//     without the deduplication step (as the source has confirmed that there are no duplicates) and the DELETE step.
	//     The data can go directly from the delta view to the base table.
	//  2. DELETE only - no INSERT or UPDATE. In this case, we can do a simple DELETE FROM in an optimized way,
	//     without the the INSERT step and the deduplication step (as the source has confirmed that there are no duplicates).
	//     The delta view can be directly used to delete rows from the base table, without the need for a temporary table.
	//  3. INSERT + non-primary-key UPDATE - no DELETE. In this case, we can skip the DELETE step.
	//     Therefore, the temporary table is not needed as the delta view will be read only once.
	//  4. The general case - INSERT, DELETE, and UPDATE. In this case, we need to create a temporary table
	//     to store the deduplicated delta and then do the INSERT and DELETE steps.

	// Identify the types of changes in the delta
	hasInserts := appender.counters.event.insert > 0
	hasDeletes := appender.counters.event.delete > 0
	hasUpdates := appender.counters.event.update > 0

	if log := ctx.GetLogger(); log.Logger.IsLevelEnabled(logrus.DebugLevel) {
		log.Debugf("Delta: %s.%s: stats: %+v", table.dbName, table.tableName, appender.counters)
	}

	withoutIndex := configuration.IsReplicationWithoutIndex()

	switch {
	case hasInserts && !hasDeletes && !hasUpdates:
		// Case 1: INSERT only
		return c.handleInsertOnly(ctx, conn, tx, table, appender, stats)
	case hasDeletes && !hasInserts && !hasUpdates:
		// Case 2: DELETE only
		return c.handleDeleteOnly(ctx, conn, tx, table, appender, stats)
	case appender.counters.action.delete == 0 && !withoutIndex:
		// Case 3: INSERT + non-primary-key UPDATE
		return c.handleZeroDelete(ctx, conn, tx, table, appender, stats)
	case withoutIndex:
		// Case 4: Without index
		return c.handleWithoutIndex(ctx, conn, tx, table, appender, stats)
	default:
		// Case 4: General case
		return c.handleGeneralCase(ctx, conn, tx, table, appender, stats)
	}
}

// Helper function to build the Arrow record and register the view
func (c *DeltaController) prepareArrowView(