Function extractTablesFromDelete

backend/plugin/parser/tidb/backup.go:188–235

(databaseName string, n *ast.DeleteStmt, fullSQL string, isCaseSensitive bool)

}

func extractTablesFromDelete(databaseName string, n *ast.DeleteStmt, fullSQL string, isCaseSensitive bool) ([]statementInfo, error) {
	cteNames := collectCTENames(fullSQL, n.Loc)
	stmtText := extractStatementText(fullSQL, n.Loc)

	singleTables := collectSingleTables(databaseName, cteNames, n.Tables, isCaseSensitive)

	if len(n.Using) == 0 {
		// Single-table DELETE: DELETE FROM t WHERE ...
		if len(singleTables) == 0 {
			return nil, nil
		}
		first := singleTables[firstKey(singleTables)]
		return []statementInfo{{
			statement: stmtText,
			table:     first,
			node:      n,
			fullSQL:   fullSQL,
		}}, nil
	}

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

	var result []statementInfo
	for _, target := range singleTables {
		name := target.Table
		if target.Alias != "" {
			name = target.Alias
		}
		ref, ok := refTables[identifierKey(name, isCaseSensitive)]
		if !ok {
			return nil, errors.Errorf("cannot extract reference table: no matched table %q in referenced table list", name)
		}
		// Skip only if the target resolves to a CTE reference (you can't delete a
		// CTE). A real table aliased with a CTE's name is still a delete target.
		if isCTERef(cteNames, ref) {
			continue
		}
		result = append(result, statementInfo{
			statement: stmtText,
			table:     ref,
			node:      n,
			fullSQL:   fullSQL,
		})
	}
	return result, nil
}

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