Basic PHP Database Operations

Accounting for 134 (experimental Class) Zheng

First, start, connect, disconnect, and stop the MySQL server

1 start

Start menu, run as input cmd press ENTER

At the command prompt, enter: net start MySQL press ENTER

2 connections

At the command prompt, enter: MYSQL-UROOT-H127.0.0.1-P press ENTER

Enter Password: 123 (server user password) press ENTER

3 disconnecting

At the command prompt, enter: quit; Press ENTER

4 Stop

At the command prompt, enter: net stop MySQL press ENTER

Second, the operation of the database

1 Creating a Database

Create database name; Press ENTER

2 Viewing the database

show databases; Press ENTER

3 Selecting a Database

Use database name; Press ENTER

4 Deleting a database

drop database name; Press ENTER

Third, the operation of the database table

The database table operation is to first select the database use database name;

1 Creating a database table

Create [temporary] table [if not EXISTS] database table name (column name 1 property, column Name 2 property ...)

Temporary use this keyword to create a temporary table

If not exists this keyword is used to avoid errors reported by MySQL when the table does not exist

The column property parameters are as follows:

Col_name Field Name

Type field types

NOT NULL | NULL is allowed as NULL, default is allow

Default value Defaults

Auto_increment indicates whether to automatically number

Primary key whether primary key

Example below:

2 View Table Structure

(1) Show columns

Show columns from data table name;

(2) describe

Describe data table name;

3 Modifying the table structure

To add a field:

ALTER TABLE data table name add column name, property;

To delete a field:

ALTER TABLE data table name drop column name;

Modify Field Name:

ALTER TABLE data table name alter old name New name;

4 Renaming a table

Rename table data table name 1 to data table name 2;

5 Deleting a table

drop table data table name;

Iv. operation of database data

1 Inserting data Insert

Insert into data table name (column name 1, column name 2,......) VALUES (value 1, value 2,......)

column names and values should correspond, data type and data one by one corresponding

2 Viewing Data Select

SELECT * from data table name; All data for the output data table name

Select [Column name 1, column name 2,......] from data table name

Where condition

GROUP BY group

Order by sort

Having a second condition

Limit limit the number of output query results;

3 Modifying Data Update

Update data table name set column name = value where condition;

4 Deleting Data delete

Delete from data table name where condition;

Basic PHP Database Operations