Tags » Primary Key

Constraints in SQL

Constraints are the rules enforced on data columns on table. These are used to limit the type of data that can go into a table. This ensures the accuracy and reliability of the data in the database. 319 more words

SQL Server

How to get a table's primary key(s) from IBMi DB2 via SQL

How to get the primary key(s) of an IBMi DB2 table via SQL.
Below is some example code on how to pull back the primary keys of a table via SQL. 521 more words


Check foreign key constraints in SQL Server Database

While searching for how to find Primary Key and Foreign Key relationship using INFORMATION_SCHEMA in SQL Server Database, I came across following query which works for me. 125 more words


When NOT to use GUID as Primary Key?

Let us first see advantages and disadvantages of GUID:

Advantages of GUID:

  1. Unique: GUID is unique across multiple every table, database, and server
  2. Merging data…
  3. 281 more words

Difference Between Primary Key and Unique Key

PRIMARY KEY UNIQUE KEY NULL It doesn’t allow Null values.
Because of this we refer 309 more words
Sql Server

Primary Key Script

The below script generates primary key across all the tables in the database.

;with CTE as (select distinct COLUMN_NAME,ORDINAL_POSITION,TABLE_NAME,b.name,c.index_id,
b. as ObjectID,b.parent_object_id as
from INFORMATION_SCHEMA.KEY_COLUMN_USAGE A Inner Join sys.key_constraints B on…
197 more words