Indexes
allow the database application to find data fast without reading the entire
table.
The CREATE
INDEX statement is used to create indexes in tables
Indexes
An index
can be created in a table to find data more rapidly and efficiently.users
cannot see the indexes, they are just used to speed up searches/queries.
SQL CREATE INDEX Syntax
Creates an
index on a table. Duplicate values are allowed:
CREATE INDEX index_name ON
table_name (column_name)
SQL CREATE UNIQUE INDEX Syntax
Creates a
unique index on a table. Duplicate values are not allowed:
CREATE UNIQUE INDEX
index_name ON table_name (column_name)
CREATE INDEX Example
The SQL
statement below creates an index named "EmpIndex " on the
"Emp_id" column in the "EmpMaster" table:
CREATE INDEX EmpIndex ON EmpMaster (Emp_id)
If you want
to create an index on a combination of columns, you can list the column names
within the parentheses, separated by commas:
CREATE INDEX EmpIndex ON EmpMaster(Emp_id, Emp_Name)
For More
details on SQL INDEX please check
