SQL Server, MySQL, Oracle syntax differences Small collection

Table operation Syntax Differences

When building a table, only the self-increment syntax is different.

The primary key (PRIMARY key), the foreign key (FOREIGN key), non-null (NOT NULL), unique (unique), and default (defaults) are the same, and the self-increment implementation is different.

The following is a list of the 3 common database-building and initialization test statements:

CREATE TABLECountry (Idint PRIMARY KEY, Namevarchar( -));CREATE TABLEPerson (Idint PRIMARY KEY, Countryidint, Namevarchar( -) not NULL UNIQUE, Sexint DEFAULT 0,  CONSTRAINTFk_cid_pidFOREIGN KEY(Countryid)REFERENCESCountry (Id));

Insert test data:

INSERT  intoCountryVALUES(1,'Shu');INSERT  intoCountryVALUES(2,'Wei');INSERT  intoCountryVALUES(3,'Wu');INSERT  intoPersonVALUES(1,1,'Liu Bei',1);INSERT  intoPersonVALUES(2,1,'Guan Yu',1);INSERT  intoPersonVALUES(3,1,'Zhang Fei',1);INSERT  intoPersonVALUES(4,2,'Caocao',1);INSERT  intoPersonVALUES(5,2,'Guo Jia',1);INSERT  intoPersonVALUES(6,2,'Code Wei',1);INSERT  intoPersonVALUES(7,3,'Sun Quan',1);INSERT  intoPersonVALUES(8,3,'Zhou Yu',1);INSERT  intoPersonVALUES(9,3,'Big Joe',2);

	Sql server	Mysql	Oracle
Self-increment	Identity (+)	Auto_increment

　　

SQL Server, MySQL, Oracle syntax differences Small collection