What are the differences between mssql and MySQL databases?

I recently summarized some practical experience in converting mssql into a MySQL database, so I will share with you today. It mainly describes the differences between mssql and MySQL databases, and these will be constantly updated. I hope you can add more information.

1. MySQL supports enum, set, and SQL server.

2 MySQL does not support nchar, nvarchar, and ntext

3. the incremental Statement of MySQL is AUTO_INCREMENT, while that of mssql is identity)

4 msms by default, the default value of the statement for creating a table everywhere is (0), but it is not allowed to contain square brackets in MySQL.

5 MySQL needs to specify the storage type for the table

6. The mssql identifier is [] and [type], indicating that it is different from the keyword, but the MySQL database is ', that is, the symbol on the left of key 1

7. mssql supports the getdate () method to obtain the current time and date. However, MySQL supports Date and Time types. The current date is cur_date (), and the current complete time is the now () function.

8 mssql does not support replace into statements, but in the latest sql20008, it also supports merge syntax

9 MySQL supports insert into table1 set t1 = '', t2 ='', but mssql does not support this write.

10 MySQL supports insert into tabl1 values)

11 mssql does not support limit statements. Unfortunately, it can only replace limt 0, N, row_number () over () with the top function to replace limit N, M

12 when creating a table in MySQL database, you must specify a storage engine type for each table, while mssql only supports one storage engine.

13 MySQL does not support the datetime-type mssql statement of the current time by default.) in MySQL, the timestamp type is used.

14. Check whether the table exists in mssql and delete it again. You need:

If exists (select * from dbo. sysobjects where id = object_id (N 'uc _ newpm ') and OBJECTPROPERTY (id, N 'isusertable') = 1)

However, in MySQL, you only need to drop table if exists cdb_forums;

15 MySQL supports unsigned integers, so it can store up to twice the maximum number of unsigned mssql statements.

16 MySQL does not support the varchar (max) type that is very convenient in mssql. This type can be used in both general data storage and blob Data Storage in mssql.

17 to create a non-clustered index in the MySQL database, you only need to specify the key when creating the table. For example, KEY displayorder (fid, displayorder) must be: create unique nonclustered index index_uc_protectedmembers_username_appid on dbo. uc_protectedmembers

(Username asc, appid asc)

18 The MySQL text field type cannot have default values

The total field length of a table in 19MySQL cannot exceed 65XXX.

20 The obvious difference is that the installation of MySQL is very simple, and the file size is only 110M non-installation version). Compared with Microsoft, the installation progress is simply .....

There are several good 21 MySQL management tools, MySQL_front, and the official suite, but they are not easy to use SSMS, which is a major disadvantage of MySQL.

22MySQL stored procedures only appear in the latest version, and the stability and performance may be inferior to mssql.

23 with the same load pressure, MySQL consumes less CPU and memory, while mssql does consume a lot of resources.

The 24php Method for connecting to the MySQL database and mssql is similar. You only need to replace the MySQL function with mssql.

25MySQL supports date, time, and year types. Only date and time are supported by mssql to 2008.