Programmer Think

1, String class Use of java.lang.String class (1) Overview String: string, represented by a pair of "" causes. String declared final, cannot be inherited String implements the Serializable interface: indicates that strings support serialization. Implemented the compatible interface: indicates that string can compare sizes ...

order This paper focuses on my SQL detecting time task of canal MysqlDetectingTimeTask canal-1.1.4/parse/src/main/java/com/alibaba/otter/canal/parse/inbound/mysql/MysqlEventParser.java class MysqlDetectingTimeTask extends TimerTask { private boolean reconnect = false; private MysqlConnection mysqlConnection; ...

I. usage You can update or insert tables from one or more sources at the same time, and delete a large amount of data that is often used to operate, that is, the efficiency is very high when updating or inserting large quantities of data. Two. Grammar merge into table_name alias1 --Alias can be used for tables requiring operations u ...

Mysql and Redis operations Mysql development Install mysql and create test library Create table mysql> CREATE TABLE `user` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `name` varchar(20) DEFAULT '', `age` int(11) DEFAULT '0', PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4; mysql> insert into user (name,age)va ...

Catalog 1. Environmental planning 2. binlog is enabled for all Mysql to ensure that the server IDs of all MySQL are different 3. The master database authorizes the master-slave replication user 4. The main database makes the database data fully available, and then pushes the backup file to the slave database 5. Restore backup files from the d ...

Introduction The Java 8 API adds a new abstraction called streaming Stream, which allows you to process data in a declarative way. Stream provides a high-level abstraction of Java set operations and expressions in an intuitive way similar to querying data from a database using SQL statements. Stream API can greatly improve the productivity of ...

An insert operation Take the simple operation of saving a record to the table as an example. Follow this example to track how the MySQL statement executes. To save a user record to the table: sqlSession.insert("x.y.insertUser", user); First of all, we need to look at the sqlsession ා insert method, and find the specific implementation in the D ...

1. Find all information about the latest employee CREATE TABLE `employees` ( `emp_no` int(11) NOT NULL, `birth_date` date NOT NULL, `first_name` varchar(14) NOT NULL, `last_name` varchar(16) NOT NULL, `gender` char(1) NOT NULL, `hire_date` date NOT NULL, PRIMARY KEY (`emp_no`)); Solution: sort order by... Desc according to the entry time in re ...

Change from: https://www.ericgg.com/archives/3848.html The default log files of springboot will not be automatically divided by day, so the log files of the production environment are getting larger and larger, which is not conducive to troubleshooting. After checking a lot of data, the final configuration is as follows. The log files can be d ...

In order to study whether sql automatic inspection and analysis tools are easy to use, I install and use soar and soar web locally. The preliminary experimental results are summarized as follows: 1. The installation is relatively cumbersome, especially the installation of dependency package of soar web, which involves the download and installat ...