How to insert ON DELETE and ON UPDATE

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I have a database structure MySQL ready, but the ALTER TABLE of FOREIGN KEY's did not specify settings for ON DELETE and ON UPDATE. How do I enter these settings now, with tables and keys already created?

mysql foreign-key

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First you would need Dropar your Foreign Key.

ALTER TABLE [Nome da sua Tabela] DROP FOREIGN KEY [Nome da sua Foreign Key];

Then you need to change the Tabela adding your key FK with the ON DELETE CASCADE

ALTER TABLE TABELA_1 
  ADD CONSTRAINT FK_NOME_SUA_FK 
  FOREIGN KEY (NOME_DA_COLUNA_QUE_SERA_FK_NA_TABELA_1) 
  REFERENCES NOME_DA_TABELA_2(NOME_DA_COLUNA_ESTRANGEIRA_DA_TABELA_2) 
  ON DELETE CASCADE;

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