First, to consolidate the advantages of index, fast data retrieval, stable query, sequential storage to avoid the server to create temporary tables, random I/O into...
GROUP_CONCAT is used together with group by to concatenate values in a column with a specified separator. The default MySQL separator is all good. The...
Int (11) represents data stored in the computer as 11 bits, for example; 00000000001, represents 1 because int occupies 4 bytes, 32 bits, and 2^32=4294967296,...
Understanding overwrite indexes starts with understanding the difference between primary and secondary indexes and how the engine works when querying. Of course, all of this...
MyCat is a completely open source, large database cluster for enterprise application development. Based on ali open source Cobar products developed. Can satisfy the database...
About MySql database, I believe many people are not unfamiliar, this is today's most commonly used a relational database, knowledge about MySql is also very...
When there are a large number of libraries or users in a database instance, permission management becomes increasingly cumbersome and may require frequent permission changes....
In the previous article, WE talked about MySQL's RR isolation level using MVCC+ next-key Locks to solve the phantom read problem. Let's take a closer...
Connection query as far as MySQL is concerned, its connection query mainly has the inner connection query, the outer connection query two kinds. Specifically in...
Mysql 5.7.29: Check the supported storage engine show Engines. InnoDB Is the default engine for Mysql. InnoDB stores tables centrally in a system table space...
Have we encountered this problem when we index a field or multiple fields in a table? The default innodb_large_prefix=0 in MySQL5.6 limits the single-column index...
MySQL storage engine architecture design, compared with other relational database management systems, such as Oracle,SQL Server and other databases, this is the biggest feature of...
Java Persistence API (JPA) is the standard specification of Java Persistence, Hibernate is the technical implementation of Persistence specification, and Spring Data JPA is a...
Database MySQL- classic eight strands one. MySQL architecture connection layer: The top layer is some clients and connection services. Service layer: Performs most of the...
A transaction is the smallest unit of execution and does not allow separation. The atomicity of transactions ensures that actions either complete completely or do...
The following address information table exists in the database. You need to implement a search for the address information that may match any information entered...