SQL statement Query Update delete

First, query statements

Get the first 10 records of data

Oracle

SELECT * from tab where rownum <= 10;

SQL Server:

Select Top Ten * from tab

Mysql:

SELECT * from tab limit 10

SELECT * FROM table name limit m,n; Starting with M, take N bar

Second, update the statement

UPDATE table name SET column name = new value WHERE Column name = value

Update < table name > set < column name > = < value > WHERE condition

Third, delete the statement

Oracle

1. D ROP To Delete a table:
DROP TABLE table_name;

2,Truncate Delete all the data in the table:
Trancate table table_name;

3. D elete to delete a row that satisfies a condition:
Delete from table_name where your_conditions;
Commit

SQL Server:

1. D ROP

DROP table TB--TB indicates the name of the data table delete the entire table (table data and table structure)

2. T runcate

TRUNCATE TABLE TB deletes the entire sheet data without deleting the table structure

3,Delete

Delete Table TB where condition Delete eligible data in table, delete by row

Mysql:

1. D ROP To Delete a table:
DROP TABLE table_name;

2. T runcate Delete all data from the table:
Trancate table table_name;

3. D elete to delete a row that satisfies a condition:
Delete from table_name where your_conditions;
Commit

SQL statement Query Update delete