DROP TABLE IF EXISTS t1; CREATE TABLE t1(c1 CHAR(10) NULL UNIQUE); INSERT INTO t1 (c1) VALUES('abc'); INSERT INTO t1 (c1) VALUES('def'); INSERT IGNORE INTO t1 (c1) VALUES('abc'); SELECT * FROM t1; c1 abc def DROP TABLE t1; CREATE TABLE t1(c1 VARCHAR(10) NULL UNIQUE); INSERT INTO t1 (c1) VALUES('abc'); INSERT INTO t1 (c1) VALUES('def'); INSERT IGNORE INTO t1 (c1) VALUES('abc'); SELECT * FROM t1; c1 abc def DROP TABLE t1; CREATE TABLE t1(c1 BINARY(10) NULL UNIQUE); INSERT INTO t1 (c1) VALUES('abc'); INSERT INTO t1 (c1) VALUES('def'); INSERT IGNORE INTO t1 (c1) VALUES('abc'); SELECT * FROM t1; c1 abc def DROP TABLE t1; CREATE TABLE t1(c1 VARBINARY(10) NULL UNIQUE); INSERT INTO t1 (c1) VALUES('abc'); INSERT INTO t1 (c1) VALUES('def'); INSERT IGNORE INTO t1 (c1) VALUES('abc'); SELECT * FROM t1; c1 abc def DROP TABLE t1;