EXPLAIN 子句其实就是用于查看当前这个 SQL 查询的逻辑计划以及优化的执行计划。 SQL 语法标准: EXPLAIN PLAN FOR <query_statement_or_insert_statement> 实际案例: public class Explain_Test { public static void main(String[] args) throws Exception { FlinkEnv flinkEnv = FlinkEnvUtils.getStreamTableEnv(arg...
public class Explain_Test { public static void main(String[] args) throws Exception { FlinkEnv flinkEnv = FlinkEnvUtils.getStreamTableEnv(args); flinkEnv.env().setParallelism(); String sql = "CREATE TABLE source_table (\n" + " user_id BIGINT COMMENT '用户 id',\n" + " name STRING ...
public class Explain_Test{public static void main(String[]args)throws Exception{FlinkEnv flinkEnv=FlinkEnvUtils.getStreamTableEnv(args);flinkEnv.env().setParallelism(1);String sql="CREATE TABLE source_table (\n"+" user_id BIGINT COMMENT '用户 id',\n"+" name STRING COMMENT '用户姓名',\n...
例public class TestExtends { public static void main(String[] args){ Student stu = new Student(); = "kk"; stu.height = 172; stu.rest(); Student stu2 = new Student("xx",150,"Science"); } } class Person{ String name; int height; public void rest(){ System.out.println("休息一...
public class Demo01 { public static void main(String[] args) { File imgFile = new File("d:" + File.separator + "001.jpg"); InputStream is = null; try { is = new FileInputStream(imgFile); } catch (FileNotFoundException e1) { ...
(SpringApplication类提供了一种便利的方式以便引导Spring应用从#main启动,大多数情况下,可以通过静态方法SpringApplication#run代理启动) How TO UseSpringApplication @EnableAutoConfigurationpublicclassMyApplication{// ... Bean definitionspublicstaticvoidmain(String[] args)throwsException { ...
public static void main(String[] args) { ServiceLoader<Car> load = ServiceLoader.load(Car.class); Iterator<Car> iterator = load.iterator(); while (iterator.hasNext()) { Car car = iterator.next(); car.getPrice(); } } } The above example briefly introduces the use of theJDK SPImechanis...
public void Base() { name = "Base class"; } public String getName() { return name; } } public class Sub extends Base { String name; public void Sub() { name="Sub class"; } public static void main(String args[]) { Base parent = new Base(); Sub child = new Sub(); ...
classAnimal{publicvoidsound(){System.out.println("Default Sound");}}publicclassDogextendsAnimal{publicvoidsound(){System.out.println("Woof");}publicstaticvoidmain(Stringargs[]){Animal obj=newDog();obj.sound();}} Abstraction:Hiding internal details and showing functionality is known as abstraction...
Myclass()获取您的cookie cutter（您的类）并使用它创建一个示例（cookie）由于main(String[] args)是...