PL/SQL 触发器从一个表上的 INSERT 更新另一个表

例如，表 A 中的列 X 是引用表 B 中的列 Y(主键)的外键.当我向表 A 添加一行时，我需要表 B 的 Z 列在 X 列 = Y 列的行中为其数值添加 1.基于我对触发器的有限理解，这是我迄今为止在 SQL 中得到的内容，以防万一(我意识到它不是很好，将其视为伪代码):创建或替换触发器 test_trig在 tableA 上插入或更新之后每行开始更新表BSET columnZ = columnZ + 1WHERE tableA.columnX = tableB.columnY;END test_trig;/谢谢 解决方案 试试这个:语法将是创建或替换触发器 test_trig在 tableA 上插入或更新之后每行开始更新表BSET columnZ = columnZ + 1WHERE tableB.columnX = :NEW.columnX;END test_trig;/:new.columnX 引用表 A columnX.I'm using SQL and an Oracle database and need some help - triggers are something I struggle to understand.I need a trigger for when I insert a row into Table A so that it updates a row on Table B: specifically the row whose primary key matches the corresponding foreign key of the row that just been added to Table A. So for example column X in Table A is a foreign key that references column Y in Table B (the primary key). When I add a row to Table A I need column Z of Table B to have 1 added to its numeric value in the row where column X = column Y.This is what I have been able to get so far in SQL based on my limited understanding of triggers, in case it helps (I realise it's not very good, treat it as pseudocode):CREATE OR REPLACE TRIGGER test_trigAFTER INSERT OR UPDATE ON tableAFOR EACH ROWBEGIN UPDATE tableB SET columnZ = columnZ + 1 WHERE tableA.columnX = tableB.columnY;END test_trig;/Thanks 解决方案 try this :Syntax will beCREATE OR REPLACE TRIGGER test_trigAFTER INSERT OR UPDATE ON tableAFOR EACH ROWBEGIN UPDATE tableB SET columnZ = columnZ + 1 WHERE tableB.columnX = :NEW.columnX;END test_trig; /:new.columnX reference the table A columnX. 这篇关于PL/SQL 触发器从一个表上的 INSERT 更新另一个表的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！