How do I set the name of a primary key when creating a table?
For example here I'm tryin开发者_开发知识库g to create a primary key with the name 'id', but this is invalid SQL. Can you tell me the correct way to do this?
CREATE TABLE IF NOT EXISTS `default_test`
(
`default_test`.`id` SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY `id`,
`default_test`.`name` LONGTEXT NOT NULL
)
Clarification
I'd like to specify the name of the primary key - rather than the default name of "PRIMARY" I'd like it to be called "id" or perhaps "primary_id", so if I were to later run SHOW INDEXES FROM default_test, the Key_name will be something I have specified.
Alternatively and more widely supported:
CREATE TABLE IF NOT EXISTS `default_test` (
`default_test`.`id` SMALLINT NOT NULL AUTO_INCREMENT,
`default_test`.`name` LONGTEXT NOT NULL,
PRIMARY KEY (`id`)
)
UPDATE
Based on the clarification, you could replace the last definition above with the following if you are to specify the index name:
CONSTRAINT `pk_id` PRIMARY KEY (`id`)
http://dev.mysql.com/doc/refman/5.1/en/create-table.html
[...] In MySQL, the name of a PRIMARY KEY is PRIMARY. [...]
CREATE TABLE IF NOT EXISTS `default_test` (
`default_test`.`id` SMALLINT NOT NULL AUTO_INCREMENT,
`default_test`.`name` LONGTEXT NOT NULL,
PRIMARY KEY (`id`)
)
You shouldn't specify the column name when you specify the primary key column name directly inline with the column definition, so:
CREATE TABLE IF NOT EXISTS `default_test` (
`default_test`.`id` SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`default_test`.`name` LONGTEXT NOT NULL
);
Alternativly you could do:
CREATE TABLE IF NOT EXISTS `default_test` (
`default_test`.`id` SMALLINT NOT NULL AUTO_INCREMENT ,
`default_test`.`name` LONGTEXT NOT NULL ,
PRIMARY KEY `default_test_id_pkey` (`id`)
);
You don't have to specify the column name again, because you already specified it as part of the current field definition - just say PRIMARY KEY
.
CREATE TABLE IF NOT EXISTS `default_test` (
`id` SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
`name` LONGTEXT NOT NULL
)
Alternatively, you can specify it separately later:
CREATE TABLE IF NOT EXISTS `default_test` (
`id` SMALLINT NOT NULL AUTO_INCREMENT,
`name` LONGTEXT NOT NULL,
PRIMARY KEY(`id`)
)
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