PG Database Source-SysCache Partial Matching Mechanism

The catcache code is located at src/backend/utils/cache/catcache.c, which contains links and operations to initialize SysCache structures and pointer relationships between data structures. Finding tuples in CatCache There are two ways to find tuples in a CatCache: exactly matching the SearchCatCache and partially matching the SearchCatcac ...

Posted by hanhao on Thu, 10 Mar 2022 19:05:13 +0100

Oracle view, index, constraint, transaction, database paradigm

๐Ÿ… Programmer Xiao Wang's blog: Programmer Xiao Wang's blog ๐Ÿ… Welcome to like ๐Ÿ‘ Collection โญ Leaving a message. ๐Ÿ“ ๐Ÿ… If you have an editor's error and contact the author, if you have a good article, welcome to share it with me, I will extract the essence and discard the dross. ๐Ÿ… Learning route of java self-study: Learning route of ...

Posted by BigX on Thu, 10 Mar 2022 17:13:11 +0100

hibernate No Dialect mapping for JDBC type 1111 problem solution

No Dialect mapping for JDBC type: 1111 problem solution Error reporting reason Because each database has its own dialect, and the simple understanding of dialect is to make a mapping relationship for the unique data types and functions of some databases, and 1111 can't find the corresponding value of dialect because there is no mapping relati ...

Posted by strangesoul on Thu, 10 Mar 2022 04:23:36 +0100

Introduction to Mybatis - adding, deleting, modifying and querying a single table based on xml configuration

ย  ย  Introduction to Mybatis - add, delete, modify and query a single table based on configuration Introduction to Mybatis Configuration steps Use steps (all xml configurations have been configured) Basic data Entity class Interface of DAO layer Master profile Sub profile Test class ย summary Introduction to Mybatis Official ...

Posted by alexrait1 on Wed, 09 Mar 2022 14:14:25 +0100

Transaction learning notes

Transaction What is a transaction? A smallest non separable work unit; Usually, a transaction corresponds to a complete business (for example, bank account transfer business, which is the smallest work unit) A complete business requires batch DML(insert, update, delete) statements to be jointly completed Transactions are only related ...

Posted by MarineX69 on Wed, 09 Mar 2022 13:00:20 +0100

MySQL has too much replication delay due to insufficient IO capacity

background Received alarm, content: MySQL_ The master-slave replication delay is too high (example: XXXX), current value: 1032.00, threshold: 1000 - 100000000, occurrence time: 12 / 30 / 2021 02:27:16. Analysis process Generally, in case of replication delay, let's first look at the replication status and active session of the slave library. ...

Posted by swasheck on Wed, 09 Mar 2022 02:35:03 +0100

node.js link database

node.js link database 1. Premise The computer has node installed. You can use the win+R key, enter cmd, and then enter node -v to check the version; Then enter npm -V to check the installed version of npm After all the above, create an empty folder named projects, which creates three empty folders: JQ, HTML and API In the jq folder, impo ...

Posted by jibosh on Tue, 08 Mar 2022 13:55:17 +0100

[track of HBase] Apache Phoenix 5.1.2 is used in detail. Like MySQL, it uses SQL statements to operate HBase (Shell operation and SpringBoot+MyBatis integration)

0. Front The previous article recorded the Shell operation and Java API operation of HBase, but the operation process is still cumbersome [track of HBase] (2) use HBase command and Java API to operate HBase (including complex query - filter and HBase tool class) It would be nice if you could write SQL operation database like MySQL, and ...

Posted by clarket on Tue, 08 Mar 2022 06:42:16 +0100

. Net/C# sub database and sub table high performance O waterfall flow paging

Frame introductionAccording to the Convention, first introduce the protagonists of this issue: ShardingCore A high-performance, lightweight solution for reading and writing separation of tables and databases under ef core, with zero dependency, zero learning cost and zero business code intrusionThe only fully automatic sub table and multi field ...

Posted by oneofayykind on Tue, 08 Mar 2022 03:46:52 +0100

MySQL data synchronization scheme practice

MySQL data synchronization scheme practice ย  prepare MySQL 5.6Canal 1.0.24Kafka 1.0.0Zookeeper 3.4.11Spring BootJDK 8IntelliJ Idea 14.1.7 background In practice, it is common for multiple systems to use the same user and other business data. With the iterative development of requirements, the number of systems increases. The business data c ...

Posted by nitram on Tue, 08 Mar 2022 03:44:32 +0100