sqlite語法備忘錄-文庫吧
2025-07-08 06:42 本頁面
【正文】 MP | TEMPORARY] TRIGGER triggername [ BEFORE | AFTER ]databaseevent ON [databasename .] tablenametriggeractionsqlstatement::=CREATE [TEMP | TEMPORARY] TRIGGER triggername INSTEAD OFdatabaseevent ON [databasename .] viewnametriggeractiondatabaseevent::=DELETE | INSERT | UPDATE | UPDATE OF columnlisttriggeraction::=[ FOR EACH ROW | FOR EACH STATEMENT ] [ WHEN expression ] BEGIN triggerstep 。 [ triggerstep 。 ]*ENDtriggerstep::=updatestatement | insertstatement | deletestatement | selectstatement例子：CREATE TRIGGER update_customer_address UPDATE OF address ON customers BEGIN UPDATE orders SET address = WHERE customer_name = 。 END。說明：創(chuàng)建了一個(gè)名為update_customer_address的觸發(fā)器，當(dāng)用戶更新customers表中的address字段時(shí)，將觸發(fā)并更新orders表中的address字段為新的值。比如執(zhí)行如下一條語句：UPDATE customers SET address = 39。1 Main St.39。 WHERE name = 39。Jack Jones39。數(shù)據(jù)庫將自動(dòng)執(zhí)行如下語句：UPDATE orders SET address = 39。1 Main St.39。 WHERE customer_name = 39。Jack Jones39。CREATE INDEX為給定表或視圖創(chuàng)建索引。語法：sqlstatement::=CREATE [UNIQUE] INDEX indexname ON [databasename .] tablename ( columnname [, columnname]* )[ ON CONFLICT conflictalgorithm ]columnname::=name [ COLLATE
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