How to make a table Read Only in SQL Server?

Question

I am updating some set of records in that table, after that I need to make this table read only.

So how to make a table Read Only in SQL Server?

Answer 1

A simple alternative that would block update and insert on a specific table but still allowing delete:

ALTER TABLE mytable WITH NOCHECK ADD CONSTRAINT chk_read_only CHECK( 1 = 0 )

Be aware: this avoids INSERTs and UPDATEs, but allows DELETEs.

If you really need a table to be truly read only you could also either:

a) put it in its own database or
b) put it on a file group and mark that read only, here’s how:

USE [master]

GO

ALTER DATABASE [csvtosp] ADD FILEGROUP [READONLYTABLES]

GO

ALTER DATABASE [csvtosp] ADD FILE ( NAME = N'mydb_readonly_tables', FILENAME = N'G:\SQL2005DATA\mydb_readonly_tables.ndf' , SIZE = 3072KB , FILEGROWTH = 1024KB ) TO FILEGROUP [READONLYTABLES]

GO

USE csvtosp

GO

DROP TABLE mytable

CREATE TABLE mytable (

    somedata    char(8000) not null

) ON READONLYTABLES

GO

For more details on this subject, go here:

How to make a table Read Only in SQL Server

Answer 2

If you want it as read only to the general public, but still want to be able to edit the table at a later date, you may want to consider creating multiple users for the database and granting different permissions to that database - ideally you should be doing this anyway and not allow the general public access to alter table, truncate etc.

Answer 3

1. Trigger with rollback trans
2. Read only filegroup
3. Don't grant insert/update/delete permissions

Number 3 is probably best practice. For example, if your connection is db_owner for example then the trigger can be disabled the trigger or move the table to a different filegroup anyway.