jdbc

问题 Is there a way in liquibase to create java code change set (i.e. provide a java class, which will receive a JDBC connection and will perform some changes in the database) ? (I know that flyway has such feature) 回答1: Yes, there is such feature. You can create a customChange: <customChange class="my.java.Class"> <param name="id" value="2" /> </customChange> The class must implements the liquibase.change.custom.CustomTaskChange interface. @Override public void execute(final Database arg0) throws

问题 There is something i don't understand with java.sql.Connection.commit() . I am using Derby(Java DB) as database server. when I do a setAutoCommit(false) , I expect my query not to work before I explicitly call the commit() method. but in fact, it still commit even if I don't call commit(). when I call a select * on my table to print the content, I can see that the rows have been added even though i didn't explicitly commit the query. Could someone give me some explanation please? con

问题 I need a JDBC driver to connect my application to Google BigQuery. I tried CData JDBC driver, but it did not support all types of Standard SQL queries. Are there any other complete options? 回答1: The official JDBC driver for BigQuery should support all types of standard SQL queries. 回答2: Are there any other complete options? You can use Query Prefix #standardSQL to force use of Standard SQL See more details in Setting a query prefix 来源： https://stackoverflow.com/questions/40538737/any-jdbc

问题 I'm learning JDBC at the moment and I already know the difference between PreparedStatement and Statement. It is that PreparedStatement is precompiled and allows you to set parameters, but I was asked a question on a job interview about difference between PreparedStatement batch and Statement batch? 回答1: The difference between batch execution of a Statement and PreparedStatement , is that a Statement batch can contain different statements (as long as they are statements that do not produce a

问题 package com.brookfieldres.operations; import java.sql.CallableStatement; import java.sql.Connection; import java.sql.Date; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Timestamp; import java.util.ArrayList; import java.util.Properties; import java.util.ResourceBundle; import org.apache.log4j.Logger; import com.microsoft.sqlserver.jdbc.SQLServerDataSource; public class SQLConnection { private static Connection acon = null; private

问题 package com.brookfieldres.operations; import java.sql.CallableStatement; import java.sql.Connection; import java.sql.Date; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Timestamp; import java.util.ArrayList; import java.util.Properties; import java.util.ResourceBundle; import org.apache.log4j.Logger; import com.microsoft.sqlserver.jdbc.SQLServerDataSource; public class SQLConnection { private static Connection acon = null; private

问题 So, I'm working from this example BONECP: package javasampleapps; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import com.jolbox.bonecp.BoneCP; import com.jolbox.bonecp.BoneCPConfig; /** A test project demonstrating the use of BoneCP in a JDBC environment. * @author wwadge */ public class BoneCPExample { /** Start test * @param args none expected. */ public static void main(String[] args) { BoneCP connectionPool = null;

问题 So, I'm working from this example BONECP: package javasampleapps; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import com.jolbox.bonecp.BoneCP; import com.jolbox.bonecp.BoneCPConfig; /** A test project demonstrating the use of BoneCP in a JDBC environment. * @author wwadge */ public class BoneCPExample { /** Start test * @param args none expected. */ public static void main(String[] args) { BoneCP connectionPool = null;

问题 This sample code is used to connect in Python to Oracle SID. import jpype import jaydebeapi jHome = jpype.getDefaultJVMPath() jpype.startJVM(jHome, '-Djava.class.path=/path/to/ojdbc6.jar') conn = jaydebeapi.connect('oracle.jdbc.driver.OracleDriver','jdbc:oracle:thin:user/password@DB_HOST_IP:1521:DB_NAME') How can we connect to Oracle Service Name? 回答1: Regarding your connection string, you could use TNS syntax (read on, here), as opposed to host:port:sid syntax you're using now. In that case

问题 What is the difference between statement.executeQuery and statement.getResultSet() . I believe both will return ResultSet for a select statement but are there any specific criteria when we should use which of them. 回答1: In general you should use executeQuery if you know you are executing a select statement. The getResultSet() method by itself does not execute the statement . The getResultSet is intended to be used in combination with execute . The execute methods are intended for use with