11-12-2012, 06:46 PM
Data Control Language in SQL
Data Control.pdf (Size: 43.41 KB / Downloads: 76)
DCL= Data Control Language
This is the third and least respected
sub-language in SQL
It is not really a security system, but
more of an access control language
Encryption is not part of the Standards
There are two kinds of people in the Schema
Users: they work with the data, but cannot
change the structure of the schema. They
write DML (Data Manipulation Language).
Admin: they can change the structure of the
schema and control access to the schema
objects. They write DDL (Data Declaration
Language).
In actual products, the lines might blur a bit
– SQL Server allows users to create temporary tables on
the fly in their sessions.
In shops, the lines might blur a bit
– One employee wears several hats
Security vs Access Control -1
Security stinks in Standard SQL
– and most products
– and most installations
If you know the schema, make a copy on a
new machine, take the existing database and
copy the file that contains the target to the
new machine.
You can loop thru values in the columns of
tables to which you have REFERENCES
privileges until you get a hit
You and conspirators can set up circular
GRANTs