To drop an index with ALTER TABLE : Alter Table « Table Index « SQL / MySQL






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To drop an index with ALTER TABLE

     
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
    -> );
Query OK, 0 rows affected (0.00 sec)

mysql>
mysql> ALTER TABLE HeadOfState ADD PRIMARY KEY (ID), ADD INDEX (LastName,FirstName);
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql>
mysql> ALTER TABLE HeadOfState DROP PRIMARY KEY;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

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








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19.The Effect of ALTER TABLE on Null and Default Value Attributes
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29.Storing Altered Character Strings
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33.Specifying Multiple Alterations
34.Alter table to add an index
35.Alter table to add unique index
36.Alter table to Delete an Index
37.Alter table to add index
38.Reduce the number of significant characters per index in the index to the first 16 characters
39.Add IGNORE to the statement, then use SELECT to have a look at the table contents to see how the duplicates ha
40.Change j from INT to BIGINT
41.MODIFY statement should specify the null and default value attributes explicitly
42.Redefine i to be NOT NULL, then try again
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