Method loadMapping

driver/mysql/binlog/binlog_reader.go:835–945

(sql, currentSchema string, schemasRenameMap map[string]string,
	oldSchemaNameToTablesRenameMap map[string]map[string]string, stmt ast.StmtNode,
	columnMap []string)

}

func (b *BinlogReader) loadMapping(sql, currentSchema string, schemasRenameMap map[string]string,
	oldSchemaNameToTablesRenameMap map[string]map[string]string, stmt ast.StmtNode,
	columnMap []string) (string, error) {

	logMapping := func(oldName, newName, mappingType string) {
		msg := fmt.Sprintf("ddl %s mapping", mappingType)
		b.logger.Debug(msg, "from", oldName, "to", newName)
	}

	// will do nothing if `table` is nil
	renameAstTableFn := func(table *ast.TableName) {
		if table == nil {
			return
		}
		table.Schema = model.NewCIStr(g.StringElse(table.Schema.String(), currentSchema))
		newSchemaName := schemasRenameMap[table.Schema.String()]
		tableNameMap := oldSchemaNameToTablesRenameMap[table.Schema.String()]
		newTableName := tableNameMap[table.Name.String()]

		if newSchemaName != "" {
			logMapping(table.Schema.String(), newSchemaName, "schema")
			table.Schema = model.NewCIStr(newSchemaName)
		}

		if newTableName != "" {
			logMapping(table.Name.String(), newTableName, "table")
			table.Name = model.NewCIStr(newTableName)
		}

	}

	renameTableFn := func(schemaName string, oldTableName *string) {
		tableNameMap := oldSchemaNameToTablesRenameMap[schemaName]
		newTableName := tableNameMap[*oldTableName]
		if newTableName != "" {
			logMapping(*oldTableName, newTableName, "table")
			*oldTableName = newTableName
		}
	}

	renameSchemaFn := func(oldSchema *string) {
		newSchemaName := schemasRenameMap[*oldSchema]
		if newSchemaName != "" {
			logMapping(*oldSchema, newSchemaName, "schema")
			*oldSchema = newSchemaName
		}
	}

	switch v := stmt.(type) {
	case *ast.DropTableStmt:
		for _, table := range v.Tables {
			renameAstTableFn(table)
		}
	case *ast.RenameTableStmt:
		for _, tt := range v.TableToTables {
			renameAstTableFn(tt.OldTable)
			renameAstTableFn(tt.NewTable)
		}