MySQL add field or create table SQL statement

Preface

Recently, we will send a message to the test and operation and maintenance department SQL Script , Used to using tools , Forget the original operation

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SQL Script

1. Add fields to existing tables

ALTER TABLE  Table name  ADD  Field name   Field type （ Field length - optional ） CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci   NOT NULL（ Can't be empty ） DEFAULT 0（ The default value is ） COMMENT ' remarks '（ remarks ）AFTER  After specifying the field （ No default last ）;

Now there is no such field in the table ：

	ALTER TABLE cl_member_wallet_withdrawal_log ADD COLUMN state char(1) DEFAULT '0' COMMENT &#