CREATE TABLE tbl_unique_test ( id INTEGER NOT NULL, value INTEGER NOT NULL DEFAULT 0, PRIMARY KEY (id) ); 挿入してみます。 mysql> INSERT INTO tbl_unique_test VALUES (1,1); Query OK, 1 row affected (0.50 sec) 同じクエリをもう一回叩いてみます。 mysql> INSERT INTO tbl_unique_test VALUES (1,1); ERROR 1062 (23000): Duplicate entry '1' for key 'PRIMARY' はい。 IGNORE を指定してみます。 mysql> INSERT IGNORE INTO tbl_unique_test VALUES (1,1)
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