Oracle drop not null constraint

The code for PDF attachment system generated via Email. Mobile Development. Software Development. Remote Development and Debugging Tools. Adding a new footer. Opening Balance. Follow us! Get the Latest Bytes Updates. By using this site, you agree to our Privacy Policy and Terms of Use. How to drop Not Null constraint system generated dgirdhar 1 Hello, I created one table say "Table1" with one column say "Column1" with constraint Not Null. Eg: If your table was like create table table1 col1 integer not null then you can use Expand Select Wrap Line Numbers Alter table table1 modify col1 integer null to remove the constraint.

Hope it helped Cheers May 21 '07 reply chandu 78 Expert Hi, If you just want to drop the not null constraint then there is a better way of doing it. In those cases, you'd need to know the name to drop it. The best advice there is to avoid the scenario by making sure you specify a name for all constraints other than "not null". Just remember, if the field you want to make nullable is part of a primary key, you can't. Primary Keys cannot have null fields.

This essentially shows a create statement for how the referenced table is made. By knowing how the table is created, you can see all of the table constraints. I was facing the same problem trying to get around a custom check constraint that I needed to updated to allow different values.

Something like that happened to me when I made copies of structures to temporary tables, so I removed the not null. Unfortunately, we cannot modify the constraint directly. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. How can I drop a "not null" constraint in Oracle when I don't know the name of the constraint? Ask Question. Asked 11 years, 9 months ago. Active 1 year, 9 months ago. Viewed k times.

Chris Farmer. Chris Farmer Chris Farmer I hope you like this article and it helps in your day to day working. Please let me know the feedback on this. Also Reads drop primary key in oracle : primary key in oracle uniquely identify the row in the table. It can be added at the time of table creation and after table is created also. Unique Key in Oracle :Unique key enforces unique in the column in the table and help us identity the row quickly. Oracle create the unique index for the key if no index available Oracle check constraint :Oracle Check Constraint are used to enforce integrity rules based on logical expressions, such as comparisons.