mysql myisam

The mysql storage engine MyISAM, InnoDB MyISAM, and InnoDB are the two most commonly used storage engines in MySQL, each having its own advantages and disadvantages. Next let's talk about them. MyISAM MyISAM is the default sto

The associated Model of thinkphp requires tables to support transactions. If my table is of the MyISAM type, isn't it necessary? How many people are using InnoDB? The associated Model of thinkphp requires tables to support transactions. If my table is of the MyISAM type, isn't it necessary? How many people are using InnoDB? Reply content: The associated Model of thinkphp requires tables to support tran

Label: ALTER TABLE????? ??? ??? ???? ?? (Heap, MyIsam, InnoDB ...)? ???? ??? ???. ?? ??? ?? ??? ??? ?? ??? ?? ????? ???? ????.[???? ?? ????]??) ALTER TABLE [????] type=[??????]"??? ???"?? Heap, MyIsam, InnoDB ...??? ???? ^^??? MyIsam?? ??? MyTable?? ???? ??? InnoDB????? ??? ????. mysql> ALTER TABLE myt

Because there is no way to add a read server in a short period of time, we have made some configuration for Mysql to sacrifice the real-time data, in exchange for the life security of all servers. The specific adjustments and ideas are as follows:MyISAM reading operations are very efficient. Once a large number of read/write concurrency occurs, the efficiency of MyISAM will decrease in comparison with InnoD

Tags: MyISAM InnoDBMyISAM① 不支持事务（事务是指逻辑上的一组操作，组成这组操作的各个单元，要么全部成功要么全部失败）。② 表级锁定（更新时锁整个表）③ 读写互相阻塞：不仅会在写入的时候阻塞读取，MyISAM还会在读取的时候阻塞写入，但读本身不会阻塞另外的读。④ 只会缓存索引：MyISAM可以通过key_buffer_size缓存索引，以大大提高访问性能，减少磁盘I/O，但这个缓存区只会缓存索引，而不会缓存数据。⑤ 读取速度较快，占用资源相对少。⑥ 不支持外键约束，但支持全文索引。⑦ 5.5.5前为默认存储引擎。适合的业务场景：1. 不需要事务支持的业务2. 读数据比较多的应用3. 数据库修改较少的业务4. 对数据一致性要求不是非常高的业务5. 硬件资源比较差

Tags: how much delete read search choose Nod table Mys atomicityInnoDB:Support transaction processing, etc.No lock ReadSupport for foreign keysSupport Row lockIndex of type Fulltext not supportedDo not save the table's exact number of rows, scan the table to calculate how many rowsDelete Table is a row of deletesInnoDB storing data and indexes in a table spaceCross-platform can be copied directly usingInnoDB must contain the index of the Auto_increment type fieldTables are hard to compressMyISAM

the index of this field. However, in the MyISAM table, you can create a joint index with other fields.4. When deleting FROM table, InnoDB does not create a new table, but deletes a row.5. the load table from master operation does not work for InnoDB. The solution is to first change the InnoDB TABLE to the MyISAM TABLE, and then change the imported data to the InnoDB TABLE, however, it is not applicable to

contain only the index of this field. However, in the MyISAM table, you can create a joint index with other fields.4. When deleting FROM table, InnoDB does not create a new table, but deletes a row.5. the load table from master operation does not work for InnoDB. The solution is to first change the InnoDB TABLE to the MyISAM TABLE, and then change the imported data to the InnoDB TABLE, however, it is not a

[Mysql] MyISAM Table Storage Format MyISAM supports three different storage formats: fixed format, dynamic format, and compressed format (only created using myisampack ). Static table features (fixed format) Static format is the default storage format for MyISAM tables. This format is used when the table does not conta

, the InnoDB must contain only the index of the field, but in the MyISAM table, you can establish a federated index with the other fields. 4.DELETE from table, InnoDB does not re-establish the table, but deletes one row at a time. 5.LOAD table from Master does not work for InnoDB, the solution is to first change the InnoDB table to MyISAM table, import the data and then change to InnoDB table, but for the u

This paper illustrates the method of MyISAM table batch compression by MySQL. Share to everyone for your reference, specific as follows: For the compression of the MyISAM table, you can use Myisampack and Myisamchk finishes (Myisampack must be myisamchk before you can use the compressed table and read-only), and its detailed usage can be referenced in the offici

Innodb:foreign key constraint system tables created 101001 21:04:31 innodb:started; Log sequence number 0 0 101001 21:04:32 [note] D:\mysql5\bin\mysqld-nt:ready for connections. Version: ' 5.0.18-nt ' socket: ' port:3306

Tags: share highlight inno ADE by SWA multiple update one Objective A lock is a mechanism by which a computer coordinates multiple processes or threads concurrently accessing a resource, and in a database, data is a resource that is shared by many users in addition to contention for traditional computing resources such as CPU, RAM, I/O, and so on. How to guarantee the consistency and validity of data concurrent access is a problem that all databases must solve, and the conflict is also

Question: Some problems are just common sense, but in some situations, "impatient" Administrators may ignore these common sense. Of course, this is also a mistake that many people will make. I would like to record this anecdote just now. Common MySQ Question: Some problems are just common sense, but in some situations, "impatient" Administrators may ignore these common sense. Of course, this is also a mistake that many people will make. I would like to record this anecdote just now. Common MySQ

Even if the MyISAM table format is very reliable (all the changes that the SQL statement makes to the table are written before the statement returns), you can still get the corrupted table if any of the following events occur: · The mysqld process was killed in the middle of writing. · Unexpected computer shutdown occurs (for example, the computer is turned off). · Hardware failure. · You can use external programs (such as MYISAMCHK) on tables tha

The difference is mainly the following points:(1) Composition, MyISAM table on disk has three files, respectively, table definition file (. frm), data file (. MYD), index file (. MYI), while the InnoDB table consists of a table definition file (. frm), tablespace data, and log files.(2) Security, MyISAM emphasizes performance, its query query efficiency is high, but does not support the transaction and fore

Tags: MyISAM logs art text tab detail efficiency net SamTransfer from http://blog.csdn.net/lingyi_xu/article/details/5393791 The difference between the InnoDB engine and the Mysiam engine Engine Transaction FOREIGN key Recommended actions INNODB Support Support Add, modify MYISAM Not supported Not supported Inquire

Label:MyISAM, InnoDB DifferenceNnodb and MyISAM are the two most common table types used by many people when using MySQL, both of which have pros and cons, depending on the application.The basic difference is that the MyISAM type does not support advanced processing such as transaction processing, and InnoDB type support. The

Tags: large storage engine It's isolated MySQL mysql store scan date logInnoDB engineThe InnoDB is a transactional storage engine designed to provide high-performance services when processing large amounts of data, which, at run time, creates buffer pools in memory for buffering data and indexes.InnoDB Engine Benefits1. Support transaction processing, acid transaction characteristics;2. The implementation o

master operation does not work for InnoDB. The solution is to first change the InnoDB TABLE to the MyISAM TABLE, and then change the imported data to the InnoDB TABLE, however, it is not applicable to tables that use additional InnoDB features (such as foreign keys.In addition, the row lock of the InnoDB table is not absolute. If MySQL cannot determine the scope to be scanned when executing an SQL statemen