Function extractTablesFromDelete

backend/plugin/parser/mysql/backup.go:126–178

(databaseName string, n *ast.DeleteStmt, fullSQL string, offset int, _ *model.DatabaseMetadata)

}

func extractTablesFromDelete(databaseName string, n *ast.DeleteStmt, fullSQL string, offset int, _ *model.DatabaseMetadata) ([]StatementInfo, error) {
	cteNames := collectCTENames(fullSQL, n.Loc)
	stmtText := extractStatementText(fullSQL, n.Loc)

	// Collect all single table refs from the Tables list.
	singleTables := collectSingleTables(databaseName, n.Tables)

	if len(n.Using) == 0 {
		// Single-table DELETE: DELETE FROM t WHERE ...
		if len(singleTables) == 0 {
			return nil, nil
		}
		for _, ref := range singleTables {
			ref.StatementType = StatementTypeDelete
		}
		first := singleTables[firstKey(singleTables)]
		return []StatementInfo{{
			Offset:    offset,
			Statement: stmtText,
			Node:      n,
			Table:     first,
			FullSQL:   fullSQL,
		}}, nil
	}

	// Multi-table DELETE: DELETE t1, t2 FROM t1 JOIN t2 ... WHERE ...
	// Tables = targets to delete from, Using = referenced table list.
	refTables := collectSingleTables(databaseName, n.Using)

	var result []StatementInfo
	for _, target := range singleTables {
		name := target.Table
		if target.Alias != "" {
			name = target.Alias
		}
		if cteNames[name] {
			continue
		}
		ref, ok := refTables[name]
		if !ok {
			return nil, errors.Errorf("cannot extract reference table: no matched table %q in referenced table list", name)
		}
		ref.StatementType = StatementTypeDelete
		result = append(result, StatementInfo{
			Offset:    offset,
			Statement: stmtText,
			Node:      n,
			Table:     ref,
			FullSQL:   fullSQL,
		})
	}
	return result, nil
}

func extractTablesFromUpdate(databaseName string, n *ast.UpdateStmt, fullSQL string, offset int, dbMetadata *model.DatabaseMetadata) ([]StatementInfo, error) {
	cteNames := collectCTENames(fullSQL, n.Loc)