mysql alter table add column

Introduction: Issues that occur on the local database execution of modifications the bank card is not error-free but online execution errorfound that the table is not found, the table name should be card_cardinfo, but there is no problem locally, can be modified, and then tested in the database, found that the local library (win) Table name is not case-sensitive,

compressed) Rows Number of rows Avg_row_length Average line length Data_length Data File Length Max_data_length Maximum data file length Index_length Index file length Data_free Allocated but not used bytes Auto_increment Next autoincrement (automatically add 1) Value Create_time Table Creation Time

Select *, (@number: = @number + 1) as number from (SelectU.mobile,u. ' Name ',ROUND((Select sum(R.realamount) fromT_recharge RwhereR.userid=U.id andR.status='1'),2) Rechargesum,ROUND((Select sum(W.realamount) fromT_withdrawal WwhereW.userid=U.id andW.status='1'),2) Withdrawalsum,ROUND(sum(F.ownamount),2) Ownamountsum,ROUND(sum(F.platformfunds),2) Platformfundssum,ROUND((Select sum(Fd.amount) fromT_fund_detail FDwhereFd.userid=U.id andFd.type='3'),2) Feesum,ROUND(sum(F.result),2) Cashre

Desc table name; show columns from table name; Describe table name; show create table table name; Use information_schemaselect * from columns where table_name = 'table name'; write down: Show databases; You can also Use informat

[MySQL FAQ] Series-Why the InnoDB table is recommended to use the self-increment column master keyHttp://imysql.com/2014/09/14/mysql-faq-why-innodb-table-using-autoinc-int-as-pk.shtmlLet's start by understanding some of the key features of the InnoDB engine

DESC table name; Show columns from table name; describe table name; Show create table name; Use Information_schema SELECT * from columns where table_name= ' table name '; By the way, note: show databases; I can do that. Use Information_schema Select Table_schema,ta

MySQL table names/column names are case sensitive. in MySQL, databases and table pairs are stored in directories and files under those directories. Therefore, the sensitivity of the operating system determines the case sensitivity of the database and

For example, my database name is example, and USEexample is used. Are you sure you want to use the example database. Use showtables; to display all tables in the database. Use DESCpersons; to display the column names in the persons table. Or use DESCRIBEpersons; or use SHOWcolumns. for example, if my database name is "example", use USE example; Are you sure you want to use the example database. Use

In Linux, the database name, table name, column name, And alias are case-sensitive: 1. The database name and table name are case sensitive; 2. Table aliases are case sensitive; 3. The column name and column alias are case-insen

MySQL uses the select statement to query the data of the specified column (field) in the specified table. This article describes how to execute a select query statement in the MySQL database to query the data of a specified column, that is, the data of a specified field. L

Desc table name; Show columns from table name; Describe table name; Show create table table name; Use information_schemaSelect * from columns where table_name = 'table name '; By the way:Show databases;You can also Use inf

]Basedir = * *Datadir= **\data4. Start MySQLI.CMD->CD **\bin->mysqld--installII. Continue to enter net start MySQL after success5. Log in to MySQLI.CMD->CD **\bin->mysql-u Root-pII. First login without password direct login successfulIII. Change the root passwordUse MySQL;Update user set Password=password ("New_pass") where user= "root";Flush privileges;Exit6. Yo

Tags: switch ast service generation REST NULL stack cannot overflowThe model cannot be generated because the following exception exists: ' System.Data.StrongTypingException: The Value of column ' IsPrimaryKey ' in table ' Tabledetails ' is DBNull. ---> system.invalidcastexception: The specified conversion is not valid. Original link Http://stackoverflow.com/questions/33575109/

Desc table name;Show columns from table name;Describe table name;Show create table name;Use information_schemaSelect * from columns where table_name = 'table name ';By the way:Show databases;You can alsoUse information_schemaSelect table_schema, table_name from tables where

Tags: i+1 tab CER IMA log query build value shareOne: the first kind: Select (@i:[email protected]+1) as I, table_name.* from table_name, (select @i:=0) as it For example: (1) Simple example: Select (@i:[email protected]+1) i,user_id from spcp_user_20170803, (select @i:=0) as it ORDER by T.user_i D desc; (2) Complex example: SELECT(@i:[email protected]+1) as i,hs_cd,hs_owner_persons,hs_owner_certy_num,hs_full_addr,t5.value_name as Hs_type, T6.value_name as Hs_owner_type,hs_use_size,hs_build_si

Solve the Problem of garbled characters in mysql table Character Set gbk, column Character Set Latin1, and python query, mysqllatin1 Recently, I encountered an abnormal problem in the company. In mysql databases, the character sets of databases and tables are both 'gbk', but the co