func()

in pkg/datasource/sql/exec/at/update_executor.go [88:136]

• 43 lines of code
• 9 McCabe index (conditional complexity)

func (u *updateExecutor) beforeImage(ctx context.Context) (*types.RecordImage, error) {
	if !u.isAstStmtValid() {
		return nil, nil
	}

	selectSQL, selectArgs, err := u.buildBeforeImageSQL(ctx, u.execContext.NamedValues)
	if err != nil {
		return nil, err
	}

	tableName, _ := u.parserCtx.GetTableName()
	metaData, err := datasource.GetTableCache(types.DBTypeMySQL).GetTableMeta(ctx, u.execContext.DBName, tableName)
	if err != nil {
		return nil, err
	}

	var rowsi driver.Rows
	queryerCtx, ok := u.execContext.Conn.(driver.QueryerContext)
	var queryer driver.Queryer
	if !ok {
		queryer, ok = u.execContext.Conn.(driver.Queryer)
	}
	if ok {
		rowsi, err = util.CtxDriverQuery(ctx, queryerCtx, queryer, selectSQL, selectArgs)
		defer func() {
			if rowsi != nil {
				rowsi.Close()
			}
		}()
		if err != nil {
			log.Errorf("ctx driver query: %+v", err)
			return nil, err
		}
	} else {
		log.Errorf("target conn should been driver.QueryerContext or driver.Queryer")
		return nil, fmt.Errorf("invalid conn")
	}

	image, err := u.buildRecordImages(rowsi, metaData, types.SQLTypeUpdate)
	if err != nil {
		return nil, err
	}

	lockKey := u.buildLockKey(image, *metaData)
	u.execContext.TxCtx.LockKeys[lockKey] = struct{}{}
	image.SQLType = u.parserCtx.SQLType

	return image, nil
}