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create table a ( a serial);
show fields from a;
Field Type Null Default Default_is_NULL On_Update
a BIGINT NO NO
show create table a;
Table Create Table
a CREATE TABLE `a` (
`a` BIGINT NOT NULL AUTO_INCREMENT,
UNIQUE KEY `a` (`a`)
) ENGINE=InnoDB COLLATE = utf8_general_ci
create table b ( b int);
show fields from b;
Field Type Null Default Default_is_NULL On_Update
b INTEGER YES YES
show create table b;
Table Create Table
b CREATE TABLE `b` (
`b` INT DEFAULT NULL
) ENGINE=InnoDB COLLATE = utf8_general_ci
create table c ( b int NOT NULL);
show fields from c;
Field Type Null Default Default_is_NULL On_Update
b INTEGER NO NO
show create table c;
Table Create Table
c CREATE TABLE `c` (
`b` INT NOT NULL
) ENGINE=InnoDB COLLATE = utf8_general_ci
create table d ( b int NOT NULL DEFAULT 10);
show fields from d;
Field Type Null Default Default_is_NULL On_Update
b INTEGER NO 10 NO
show create table d;
Table Create Table
d CREATE TABLE `d` (
`b` INT NOT NULL DEFAULT '10'
) ENGINE=InnoDB COLLATE = utf8_general_ci
create table e ( b int DEFAULT NULL);
show fields from e;
Field Type Null Default Default_is_NULL On_Update
b INTEGER YES YES
show create table e;
Table Create Table
e CREATE TABLE `e` (
`b` INT DEFAULT NULL
) ENGINE=InnoDB COLLATE = utf8_general_ci
drop tables a,b,c,d,e;
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