MySQL Drop Constraint Syntax Error -

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i'm using mysql 5.1.36 i'm trying drop constraint named chk1 mysql reports syntactical error. looked unable find it. error?

mysql> create database house; query ok, 1 row affected (0.01 sec) mysql> use house; database changed mysql> create table member(age integer); query ok, 0 rows affected (0.05 sec)  mysql> alter table member add constraint chk1 check(age>0); query ok, 0 rows affected (0.08 sec) records: 0  duplicates: 0  warnings: 0  mysql> alter table member drop constraint chk1; error 1064 (42000): have error in sql syntax; check manual corresponds mysql server version right syntax use near 'constraint chk1' @ line 1  mysql> alter table member drop check chk1; error 1064 (42000): have error in sql syntax; check manual corresponds mysql server version right syntax use near 'check chk1' @ line 1

check constraint parsed ignored in mysql. don't need remove it. can use enum or triggers implement desired functionality. in case can change age unsigned.


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