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Public Number: Madad's Technical Wheel Sharing mainly uses ANTLR4 to parse SQL. Take mysql as an example, before analyzing the source code, we can first understand the following three points: antlr4, how to write.g4 grammar file The mysql grammar can be referred to https://dev.mysql.com/doc/refman/8.0/en/sql-syntax-data-manipulation.html ...

At the beginning, I spent half a day searching for sharding-sphere on the Internet and reading the source code for half a day (trying to use the @Configuration annotation instead of writing configuration files, I think there are too many configuration files, which are dazzling), and I didn't understand why. Later, I found a more complete answe ...

Zabbix has no report export function, so it exports ZABBIX data and sends mail concurrently by writing scripts. The results are as follows: [External Chain Picture Transfer.. (img-YujWHCbu-1565876650802)] Following is the script, which can be modified according to its own specific circumstances: `#!/usr ...

IF Tags Problems arising from the non-use of if tags Dynamic splicing sql is realized by various tag methods provided by mybatis. Demand: user enquiry based on gender and name Query sql: SELECT id, username, birthday, sex, address FROM user WHERE sex = 1 AND username LIKE'% Liu%' <!-- Query users b ...

Links to the original text: https://my.oschina.net/qiuzhping/blog/611700 ExtJs 4.2 Application: Extending component search field with ExtJs Implementing Data Search Function 1. Int ...

Specifications dynamic query Sometimes when we query an entity, the given condition is not fixed, so we need to dynamically construct the corresponding query statement. In Spring Data JPA, we can query through Jpa Specification Executor interface. Compared with JPQL, its advantage is type-safe and mor ...

What is it? One kind of database connection pool, manages and releases the connection of database, realizes the reuse of connection, and can compare thread pool. Parameter configuration What can we do? 1, Connection Pool 2, Monitoring 3, Encryption 4, Extending JDBC How do you use it? Adding ...

Read the official document before analyzing the source code Read / write separation Major Records Learn, Public Number: Madad's Technical Wheel Core concept Main library: add, update and delete data operations Slave library: The database used to query data operations, which can support multiple slave Libraries Multi-master and multi-slav ...

Druid is provided by the C3P0, and the specific operation steps are very similar to those of the C. We will copy the downloaded Druid directly into the IDEA tool Druid's configuration file is in the form of properties. Its configuration file can be called any name and can be placed in any directory. It ...

The evaluation is not very pleasant, but it has to be used. Translated Documents: Although the version is very old, it is still valuable. https://vibrantlink.com/pun_multiplay_manual/?tdsourcetag=s_pcqq_aiomsg   Common api memo Custom classes inherit from Photon.PunBehaviour Join the room: Phot ...