table cache mysql

MySQL Query Cache Query_cache_size Starting with MySQL 4.0.1, MySQL server has an important feature: Query Cache. When in use, the query cache stores the text of a SELECT query and the corresponding results that are delivered to

stating that the query cache is not allowed, or if you have explicitly declared that you need to use query cache), MySQL will hash the received SELECT statement as a string directly based on a pre-set hash algorithm, and then go directly to the query cache to find out if it is already cached. That is, if it is already

MySQLQueryCache (cache) bitsCN.com MySQL Query Cache) SQL code www.bitsCN.com # Example MySQL config file for medium systems. # The application is generated by mysql-5.1.37-win32 editing of the my-medium.ini on one machine. # This is for a system with little memory (32 M-6

. Each user login to use the query, are not the same SQL text, QC here is almost useless, because the cached data is almost not used, they will only occupy a place in memory. Negative effects of 2,querycache:1,query hash performance problem and hit rate problem;2, the query cache and its easy invalidation, when the table content changes or the table structure cha

"Go" BusyBox analysis--arp set the MAC address in the ARP cache tableTransferred from: http://blog.chinaunix.net/uid-26009923-id-5098083.html1. Modify the MAC address of an IP in the ARP cache table[emailprotected]:/work/test/tcpip/busy/arp$ cat arp.c #include "utils.h" #include 3. Execution results [Emailprotected]:/work/test/tcpip/busy/arp$ Cat/proc/net/arp |

/MY.CNF[MYSQLD] Added: Query_cache_type = OnHave_query_cache indicates whether the current database supports caching capabilities; YesQuery_cache_limit represents the maximum value of a single query cache, and if the query results exceed this size, the result is not cached even if the current result is specified; default is 1MQuery_cache_min_res_unit indicates that the cache is stored in memory of the small

connection can improve the load when connecting to the database, it consumes a lot of memory resources. if a large amount of data is obtained, the storage duration will be very short.Create an SQL query:SQL (Structured Query Language) queries are used as interfaces to operate databases and their content. SQL can be used to define and edit the table structure, insert data to the table, and update or delete

Filter all comments Remove the space before the SQL text, tab, and so on. Note that the front and rear of the text. The middle will not be removed. In the following three SQL, because of the Select Case relationship, the last one and the other two are definitely different storage locations in the QC. And the first and second, the difference is that the latter have a comment, in different clients, there will be the same result. So, to be on the safe side, please try not to use dynamic annotatio

procedure in a query statement;The statement with lock in SHARE MODE and for update is used in the query statementSimilar to select in query statement ... Into the statement of the exported data;Transaction ISOLATION LEVEL is: Serializable case, all query statements can not be cached;Query operations on temporary tables;A query statement that has a warning message;A query statement that does not involve any table or view;A user only has Column Level

Create a table for the cache Database 1. Create a table by creating a class 2. Modify your own package and Class Name 3. Select a persistent class 4. Table Name 5. Create a table attribute. One attribute is a column of the table

Detailed description of MySQL query Cache Query cache stores the text returned to the client using the SELECT syntax query. When the same request occurs again, data is retrieved from the query cache instead of being queried again. The query cache is shared Session, so the re