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configuration file The name must be c3p0-config.xml, otherwise it cannot be found; <default-config> is also indispensable. Label name <c3p0-config> <default-config> Specific configuration content </default-config> </c3p0-config> Generally according to the above configurati ...

When using ResultSet to receive a result set from a database query, even if the result set has only one data, the resultSet.next() function is needed to move the cursor to get the data. Otherwise, the ResultSet.next exception will be reported not to be invoked. Wrong writing try { pstm=connection.prepareStatement("selec ...

introduce Fast-family-data source is a multi-data source processing module in fast-family framework. It provides XA distributed transaction processing, annotations specify data sources, and simple configuration file pointing can complete multi-data sources and transaction management. Note: For the time being, only druid data sources are support ...

Summary DBUtils is a practical tool for database operation in Java programming. It is compact, simple and practical. DBUtils encapsulates the operation of JDBC, simplifies the operation of JDBC, and can write less code. Introduction to Three Core Functions of DBUtils API to provide operations on sql statements in Query Runner ResultSetHan ...

Incremental import Incremental import append for incremental columns # First import [root@node222 ~]# /usr/local/sqoop-1.4.7/bin/sqoop import --connect jdbc:mysql://192.168.0.200:3306/sakila?useSSL=false --table actor --where "actor_id < 50" --username sakila -P --num-mappers 1 --target-dir /tmp/hive/sqoop/actor_all ... 18/10/1 ...

Catalog Overview of Spring JDBC Framework JdbcTemplate class Configuring data sources Data Access Object (DAO) Execute SQL commands Overview of Spring JDBC Framework Using traditional JDBC to connect databases, it becomes very troublesome to write unnecessary code to handle exceptions, open and close database connections, etc. However, the ...

This video viewing address: https://edu.51cto.com/sd/3ec2c 1. Caching 1.1. The Significance of Caching By putting the data that users often query in the cache (memory), users can query the data from the cache instead of from the disk (relational database data files), thus improving the query efficiency and solving the performance problems of ...

I. Propertie It is mainly used for reading and writing resource configuration files. Properties inherit from Hashtable. Let's look at the difference between HashMap and Hashtable: Hashtabl is thread-safe, synchronous and inefficient. HashMap threads are insecure, asynchronous and efficient.   Neither Hashtable key nor value can be empty ...

1. Automatic Configuration of Transaction Manager 1 Description When using JDBC as data access technology, Spring Boot defines a Bean for Platform Transaction Manager to implement DataSource Transaction Manager. When using JPA as database access technology, Spring Boot defines a Bean for Platform Transaction Manager to imple ...

StartSonar.bat cannot start in Sonarqube. Win10 Problem Description and Final Solution Establishing Sonar database Modify the configuration file conf sonar. properties Problem Description and Final Solution 1. Download MySql 5.7.23, Sonar 6.7.5 2. Following the installation documents on the Internet, the Sonar database ...