mysql pivot table

Tags: dump table data cipher Table data nbsp database name Database mysqldumpThe following command-line specific usage is as follows: Mysqldump-u user name-p password-d database name name Script name;1, the Export database is DBNAME table structure (where the user name is root, password is dbpasswd, the generated script name is Db.sql)Mysqldump-uroot-pdbpasswd-d

MySQL sub-table method:Method One, do the database cluster! Master-Slave database bidirectional hot backup (or one-to-many database real-time backup strategy), which can allocate database queries to several servers (can be combined with server load Balancing architecture)Pros: Good extensibility, no complex operations after multiple tables (PHP code)Cons: The amount of data in a single

Tags: style color using AR strong file SP data onMyISAM Data Sheet After you delete the largest numbered record, the number is not reusable. You can use the "auto_increment=n" option to specify a self-increment initial value when building a table. Use the ALTER TABLE TABLE_NAME AUTO_INCREMENT=N command to reset the starting value of the increment. Other: The self-increment field is not contiguous because s

A few days ago wrote a MySQL cross table update of a summary, today we look at the cross table delete. After Mysql4.0, MySQL begins to support the cross table delete. MySQL can delete multiple

The two databases in mysql have different table structures. how can we import data from one table to another? mysql has different structures in the two databases. how can we import data from one table to another? Reply to discussion (solution) If the

View the information of the mytable table 1. view the storage engine and number of records of a table. Mysql> show table status like 'mytable' \ G; * *************************** 1. row ************************** Name: mytable # table Name Engine: innoDB # storage engine Inno

MySQL transaction table and non-transaction tableMySQL transaction table and non-transaction tableWhen viewing the max_binlog_stmt_cache_size parameter explanation, there is such a sentence If nontransactional statements within a transaction require more than this has bytes of memory, the server generates an error.So what is nontransactional statements?In the htt

Export:The following command-line specific usage is as follows: Mysqldump-u user name-p password-d database name name Script name;1, export the database to DBNAME table structure (where the username is root, password is dbpasswd, the generated script name is Db.sql)Mysqldump-uroot-pdbpasswd-d dbname >db.sql;2. Export the database to dbname a table (test) structureMysqldump-uroot-pdbpasswd-d dbname test>db.s

Tags: des style blog color ar using SP data divDescribe statement:Grammar:describe table name;Simplified notation:desc Table NameAttention1. Two kinds of writing results are the same,2. You can not end with a semicolon,3. Multiple tables are not supported for simultaneous querying.Detailed structure of query table creation:Code:Create

MySQL study Note 5: modifying the table (altertable) bitsCN.com we will inevitably consider the week before creating the table. Therefore, the alter table statement is required to modify the table later. Modify table name

table, for example forums causes a row in the messages table to point to the forums table that is not in, and we want the database to automatically delete all messages that belong to the table when we design the Web application, then we can further modify the foreign key constraint. Let him perform a cascade delete. W

Mysql performance optimization 3 (Table sharding, Incremental backup, and restoration), mysql Performance OptimizationHorizontal table Division If a table contains too many records, for example, tens of millions of records and needs to be searched frequently, it is necessary

Thinkphp Associated Model Association operation requires table support transactions Ah, my table is MyISAM type that's not going to work? How many people are using InnoDB now? Reply content: Thinkphp Associated Model Association operation requires table support transactions Ah, my table is MyISAM type that's not

MySQL Tutorial PHP tutorial dynamically add Column ALTER table to tableAdd the MySQL statement of the column asALTER TABLE tablename ADD COLUMN columnName varchar () NOT NULL*/Database Tutorial Connection method$db = ' 111cnNet ';$conn = mysql_pconnect (' localhost ', ' root ', ' root ') or Die (Mysql_error ());mysql_s

If the fields of the 2 tables are consistent and you want to insert all the data, you can use this method: Code: Copy Code code as follows: INSERT into target table SELECT * from source table; For example, to insert a articles table into the Newarticles table, you would: Copy Code code as follows:

Learning Addresshttp://www.jtthink.com/course/play/352Main Table: Prop_mainDo not say more carefully, normal business will be involved and considered relatively comprehensive. Characters commonly used segment "Product ID" "Product name" "Product Profile" "Product category" "Add Time" "hits/Likes/purchases/bad reviews"The point is that "clicks/likes/purchases/Bad reviews" are updated regularly. But for speed and efficiency when reading, it is very scie

single-table only query by: DISTINCTUnique query for multiple tables: Group byDistinct when querying multiple tables, the LEFT join is valid and the full connection is invalid.When using MySQL, it is sometimes necessary to query for a record that does not duplicate a field, although MySQL provides the DISTINCT keyword to filter out redundant duplicate records to

An instance that causes damage to the mysql data table after an illegal shutdown solves bitsCN.com Troubleshooting of data tables: 1. when you access the webpage, an error is displayed, indicating that the database cannot be connected. 2. start the mysql service and uninstall and disable the mysql service installed by

Java -- mysql -- get all table names and table field names ., Mysqltable Obtain the names of all tables in the database: (Reference: http://stackoverflow.com/questions/2780284/how-to-get-all-table-names-from-a-database) DatabaseMetaData md = conn.getMetaData();ResultSet rs = md.getTables(null, null, "%", null);while (r

1. Copy table structure and data to new table Copy Code code as follows: CREATE Table New Table SELECT * from old table 2. Copy table structure to new table