Flink SQL:CREATE Statements

CREATE Statements

CREATE statements are used to register a table/view/function into current or specified Catalog. A registered table/view/function can be used in SQL queries.
CREATE语句用于将表/视图/函数注册到当前或指定的目录中。注册的表/视图/函数可以用于SQL查询。

Flink SQL supports the following CREATE statements for now:
Flink SQL目前支持以下CREATE语句：

• CREATE TABLE
• CREATE CATALOG
• CREATE DATABASE
• CREATE VIEW
• CREATE FUNCTION

Run a CREATE statement

Java
CREATE statements can be executed with the executeSql() method of the TableEnvironment. The executeSql() method returns ‘OK’ for a successful CREATE operation, otherwise will throw an exception.
CREATE语句可以使用TableEnvironment的executeSql()方法执行。executeSql()方法为成功的CREATE操作返回“OK”，否则将引发异常。

The following examples show how to run a CREATE statement in TableEnvironment.
以下示例演示如何在TableEnvironment中运行CREATE语句。

TableEnvironment tableEnv = TableEnvironment.create(...);

// SQL query with a registered table
// register a table named "Orders"
tableEnv.executeSql("CREATE TABLE Orders (`user` BIGINT, product STRING, amount INT) WITH (...)");
// run a SQL query on the Table and retrieve the result as a new Table
Table result = tableEnv.sqlQuery(
  "SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'");

// Execute insert SQL with a registered table
// register a TableSink
tableEnv.executeSql("CREATE TABLE RubberOrders(product STRING, amount INT) WITH (...)");
// run an insert SQL on the Table and emit the result to the TableSink
tableEnv.executeSql(
  "INSERT INTO RubberOrders SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'");

SQL CLI
CREATE statements can be executed in SQL CLI.
CREATE语句可以在SQL CLI中执行。

The following examples show how to run a CREATE statement in SQL CLI.
以下示例显示了如何在SQL CLI中运行CREATE语句。

Flink SQL> CREATE TABLE Orders (`user` BIGINT, product STRING, amount INT) WITH (...);
[INFO] Table has been created.

Flink SQL> CREATE TABLE RubberOrders (product STRING, amount INT) WITH (...);
[INFO] Table has been created.

Flink SQL> INSERT INTO RubberOrders SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%';
[INFO] Submitting SQL update statement to the cluster...

CREATE TABLE

The following grammar gives an overview about the available syntax:
以下语法概述了可用语法：

CREATE TABLE [IF NOT EXISTS] [catalog_name.][db_name.]table_name
  (
    { <physical_column_definition> | <metadata_column_definition> | <computed_column_definition> }[ , ...n]
    [ <watermark_definition> ]
    [ <table_constraint> ][ , ...n]
  )
  [COMMENT table_comment]
  [PARTITIONED BY (partition_column_name1, partition_column_name2, ...)]
  WITH (key1=val1, key2=val2, ...)
  [ LIKE source_table [( <like_options> )] ]
   
<physical_column_definition>:
  column_name column_type [ <column_constraint> ] [COMMENT column_comment]
  
<column_constraint>:
  [CONSTRAINT constraint_name] PRIMARY KEY NOT ENFORCED

<table_constraint>:
  [CONSTRAINT constraint_name] PRIMARY KEY (column_name, ...) NOT ENFORCED

<metadata_column_definition>:
  column_name column_type METADATA [ FROM metadata_key