if [ $ = $ ] then echo "ALTER TABLE SYSADM.$ DROP CONSTRAINT $;" $_$Disable a constraint associated with a table: Syntax: DISABLE
Since neither of these solutions is particularly satisfactory Oracle 8i includes support for deferred constraints.
A deferred constraint is only checked at the point the transaction is commited.
For a UNIQUE constraint, this enables you to load data from a nonpartitioned table into a partitioned table using the ALTER TABLE.. When a unique or primary key is Enabled, if there is no existing index, a unique index is automatically created.
When a unique or primary key is Disabled, the unique index is dropped.
The constraint should make the PRODUCT_NAME unique.
I've tried it with the following statement: Your question is not clear. If you have duplicate values in a column then you cannot enforce a UNIQUE constraint on it.
If you define a constraint but do not explicitly enable or disable it, ORACLE enables it by default.
Any SQL INSERT, UPDATE or DELETE command applied to a table with constraints enabled has the possibility of failing.
For example, updates applied to a Parent Table may fail if the statement leaves orphaned rows in a child table, INSERT command against a Child Table may fail if a matching foreign key value does not exist in the parent table.