Examples of common SQL database commands and syntax

1. Add (insert a record into the database).

insert into the table name (column name 1, column name 2, column name 3......)values('Value 1,'Value 2','Value 3'……)

Example: insert into muser(id,name,pwd).

values('1','admin','admin')

Note: The number of columns must be the same as the number of values given in the values clause. The data type must correspond to the data type of the class.

2. Delete (delete data from the table).

The delete statement is used to delete data, either one row at a time or multiple rows.

Basic syntax for delete statements:

delete from table name where condition.

Example: delete from muser where id='1' and pwd='admin'

3. Update (modify the data in the table).

The update statement is used to modify existing data, and the update statement can affect one row, multiple rows, or even all data.

The basic syntax of the update statement:

update table name set

Column name ='The data that needs to be modified is required'

where modifies the condition.

Example: Update muser set

pwd='admin888'

where name='admin' and pwd='admin'

4. Check (use select to query the database).

The select statement is mainly used to retrieve data.

The basic syntax of the select statement:

select column name.

from the table name.

where the criteria of the retrieval.

Example: select * from news where class='Domestic news'

The use of (*) in the column name indicates that all columns specified from the from table are returned.

What are the commands for those databases you want to ask?

Is it a query? Operational or administrative?

Select, update, insert, deletealter, create, drop, lock table, and management commands, MySQL, Oracle, SQL Server database commands are different.

select * from indication.

update table name.

set field=''

where condition.

delete from table name where condition.