To create a unique-valued index, use the UNIQUE keyword instead of INDEX. : Index « Table Index « SQL / MySQL






To create a unique-valued index, use the UNIQUE keyword instead of INDEX.

    
mysql>
mysql> CREATE TABLE HeadOfState
    -> (
    ->     ID           INT NOT NULL,
    ->     LastName     CHAR(30) NOT NULL,
    ->     FirstName    CHAR(30) NOT NULL,
    ->     CountryCode  CHAR(3) NOT NULL,
    ->     Inauguration DATE NOT NULL,
    ->     UNIQUE (ID)
    -> );
Query OK, 0 rows affected (0.01 sec)

mysql>
mysql> drop table HeadOfState;
Query OK, 0 rows affected (0.00 sec)

   
    
    
    
  








Related examples in the same category

1.Creating a Table with an Index
2.Create table: alter table to drop index
3.Create index on a column
4.Create table: Make index
5.Create index on table column with order
6.Create index on one column
7.Create index on two columns
8.Create unique index on table columns
9.Create index using btree
10.Handling Duplicate Index Values
11.Eliminating Duplicates by Adding an Index
12.How to include a unique index in the table definition.
13.How to include a regular index in a table definition:
14.Get the descriptive data of the indexes defined on the PENALTIES table.
15.Creating Indexes (CREATE INDEX)
16.Create an index on the AMOUNT column of the PENALTIES table.
17.Get the names of the indexes defined on the PENALTIES table.
18.Defining Indexes at Table-Creation Time
19.The syntax for CREATE INDEX is as follows
20.Removing Duplicates by Adding an Index
21.Removing Indexes
22.Create index of decimal type column
23.Create view for indexes
24.Drop an index by name
25.Add index to int type column
26.PRIMARY KEY INDEX_PRIM
27.Create an index and check it
28.Adding or Dropping Indexes
29.There are four types of statements for adding indexes to a table:
30.Hash index
31.Show index for a table
32.Using index in order by clause to indecate the result from subquery
33.Create a table with a nonunique index on the date-valued column Inauguration
34.To include multiple columns in an index
35.Provide index definitions in addition to the column definitions.
36.Modifying Indexes of Existing Tables
37.A table can have multiple indexes.
38.Create a single-column index on c, and the second creates a multiple-column index that includes both c and i