CREATE INDEX `indexs` ON `testtable` (`pass`);

DROP TABLE `testtable`;

CREATE TABLE `testtable`

(

`id` INT(42),

`user` TEXT,

`pass` VARCHAR(10) NOT NULL,

PRIMARY KEY(`id`)

);

CREATE INDEX `indexs` ON `testtable` (`pass`);

DESCRIBE `testtable`;

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DROP TABLE `testtable`;  CREATE TABLE `testtable` ( `id` INT(42), `user` TEXT, `pass` VARCHAR(10) NOT NULL, `age` INT(3), PRIMARY KEY(`id`) );  CREATE INDEX `indexs` ON `testtable` (`pass`,`age`);  SHOW INDEXES FROM `testtable`; 

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DROP TABLE `testtable`;  CREATE TABLE `testtable` ( `id` INT(42), `user` TEXT, `pass` VARCHAR(10) NOT NULL, `age` INT(3), PRIMARY KEY(`id`) );  CREATE UNIQUE INDEX `indexs` ON `testtable` (`pass`,`age`);  #DESCRIBE `testtable`; SHOW INDEXES FROM `testtable`;

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ALTER TABLE `testtable` DROP COLUMN `age`;   DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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ALTER TABLE `testtable` ADD COLUMN `age` INT(5);   DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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ALTER TABLE `testtable` ALTER COLUM `age` `age` INT(10);   DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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ALTER TABLE `testtable` CHANGE `age` `age` INT(10);   DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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ALTER TABLE `testtable` DROP INDEX `indexs`;   DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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DROP TABLE `testtable`;  CREATE TABLE `testtable` ( `id` INT(42) NOT NULL AUTO_INCREMENT, `user` TEXT, `pass` VARCHAR(10) NOT NULL, `age` INT(3), PRIMARY KEY(`id`) );  DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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DROP TABLE `testtable`;  CREATE TABLE `testtable` ( `id` INT(42) NOT NULL AUTO_INCREMENT, `user` TEXT, `pass` VARCHAR(10) NOT NULL, `age` INT(3), PRIMARY KEY(`id`) );   ALTER TABLE `testtable` AUTO_INCREMENT=100;  DESCRIBE `testtable`; #SHOW INDEXES FROM `testtable`;

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IS NOT NULL

SELECT * FROM  `users` WHERE `id` IS NOT NULL;

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