最有效的方法来从3列更新一列

Question

这是从三个不同列更新单个列的最有效方法吗？

UPDATE TBL_FR2052A_TPOS_HIST_SPLIT
SET REPORTABLE_AMOUNT = ISNULL(PRINCIPAL,0)

UPDATE TBL_FR2052A_TPOS_HIST_SPLIT
SET REPORTABLE_AMOUNT = ISNULL(INTEREST,0)

UPDATE TBL_FR2052A_TPOS_HIST_SPLIT
SET REPORTABLE_AMOUNT = ISNULL(RAW_DATA_AMOUNT,0)

我正在使用SQL Server.谢谢!

Answer 1

看起来像COALESCE()会有所帮助

UPDATE TBL_FR2052A_TPOS_HIST_SPLIT
SET REPORTABLE_AMOUNT = COALESCE(ROW_DATA_AMOUNT, INTEREST, PRINCIPAL, 0)

REPORTABLE_AMOUNT然后将使用COALESCE()非空的第一个值进行更新.