mysql syntax

5 Table Management Select Database5.1 View all tables Mysql> Show tables;+-----------------+| TABLES_IN_DAY15 |+-----------------+| Student |+-----------------+1 row in Set (0.00 sec) 5.2 Creating a table

http://blog.csdn.net/pipisorry/article/details/46764495MySQL Common display command1. Displays the list of databases in the current database server:mysql> SHOW DATABASES;Note: MySQL library has the MySQL system information, we change the password

description of MySQL data_add function and date format function Date_add (date, INTERVAL expr type) date_sub (date, INTERVAL expr type ) These functions perform date operations. Date is a DATETIME or date value used to specify the

Create Table 'User'('ID' int(Ten) not NULL,'username' varchar( -) not NULL,'Password' varchar( -) not NULL,Primary Key('ID'),Unique Key 'username');Reason for error: Remove the single quotation mark and change to the followingMysql> CREATE TABLE

1 Create proceduregh () #注意各个地方的分号! This code should run the section that removes the last sentence, and then run call GH to display the results that have been stored2 BEGIN3 DeclareC_noint; #声明数据类型的方法4 5 Select Count(*) intoC_no # Depositing a

11. Add DataAn existing student table is designed as follows:Sno Primary KEY and self-increment, saddress represents the address, set the default value: ' Guangdong province Guangzhou '1. Add a complete insert into tables values (Val1,val2,..., valn)

Comparison operators: =, >, =, ,! =, select AVG (col_name) from Tb_name; # Use aggregate functions for specified fieldsSELECT ROUND (AVG (Col_name), 2) from Tb_name; # retain two decimal places for

Six. Aggregation functionUsing the aggregation function, you can easily analyze the data, mainly have the following application scenarios:1. Determine the number of rows in a table (statistics)2. Sum the values of a column3. Find the table column

"Copyright Notice: respect for the original, reproduced please retain the source: blog.csdn.net/shallnet, the article only for learning Exchange, do not use for commercial purposes"SQL (Structured Query language) is a database query and programming

Environment: mysql 5.5 Create Database test: test; We can execute the code to create the test database. If you want to check whether the database test has been created, you can use the code to view all the databases in mysql. show databases; What

In actual development, you always encounter this situation. Or in this case If you are still using select fields from table where like '/%', it is definitely a thankless practice, taking a closer look at the built-in functions of MYSQL is

I want to get started with all the languages I want to learn. mysql is also the same as it is with basic syntax and data types. Let's take a look at the simple mysql tutorial.MySQL syntax The great thing you do in MySQL is that the "code" is easy to

Database selection, creation, discarding and changing the creation of data tables and indexes, changing and discarding the retrieval information from data tables Database selection, creation, discarding and changing the creation of data tables and

SELECTfunction_baseurl.idASidFROMfunction_baseurlWHERETRUE: the code of a colleague added a backslash to all the fields, making the code very ugly. what is the significance of this operation? SELECT Function_baseurl. IdAS IdFROM

MySQL provides this very powerful thing, but the documentation has limited instructions, so that you may doubt MySQL's capabilities! Is a session-level quasi-system variable generated, maintained, and recycled by the server similar to MySQL

1、错误查询语句：$sql='select * from sh_admin where username=$username and password=$password limit 1';2、正确查询语句：$sql = "select * from sh_admin where username = '{$username}' and password = '{$password}' limit 1"; When PHP operation MySQL database Why must

First look at the classification of SQL statements supported by MySQL 1, database selection, creation, discard and change Use Create Database Drap Database ALTER DATABASE 2, data table and index creation, change and discard CREATE table drop

In actual development, you will always encounter this situation or in this situation. If you're still using the Select fields from table where you like '/% ' is definitely a thankless practice, then it's definitely a priority to study MySQL's

MySQL CONCAT (str1,str2,...)Returns the string that results from the connection parameter. If any one of the arguments is NULL, the return value is null. There may be one or more parameters. If all parameters are non-binary strings, the result is a

Defined:The first type:Case Case_value while When_value then statement_list [when When_value then Statement_list] ... [ELSE Statement_list] END caseThe second type:When the case is search_condition then statement_list [when