tencent cloud

CREATE TABLE 表名
  (
    { <列定义> | <计算列定义> }[ , ...n]
    [ <Watermark 定义> ]
    [ <表约束定义, 例如 Primary Key 等> ][ , ...n]
  )
  [COMMENT 表的注释]
  [PARTITIONED BY (分区列名1, 分区列名2, ...)]
  WITH (键1=值1, 键2=值2, ...)
  [ LIKE 其他的某个表 [( <LIKE 子句选项> )] ]

<列定义>:
  列名 列类型 [ <列的约束定义> ] [COMMENT 列的注释]

<列的约束定义>:
  [CONSTRAINT 约束名] PRIMARY KEY NOT ENFORCED

<表的约束定义>:
  [CONSTRAINT 约束名] PRIMARY KEY (列名1, 列名2, ...) NOT ENFORCED

<计算列定义>:
  列名 AS 计算列表达式 [COMMENT 列的注释]

<Watermark 定义>:
  WATERMARK FOR 某个Rowtime类型的列名 AS 某个Watermark策略表达式

<LIKE 子句选项>:
{
   { INCLUDING | EXCLUDING } { ALL | CONSTRAINTS | PARTITIONS }
 | { INCLUDING | EXCLUDING | OVERWRITING } { GENERATED | OPTIONS | WATERMARKS } 
}[, ...]

WATERMARK FOR 某个Rowtime类型的列名 AS 某个Watermark策略表达式

CREATE TABLE StudentRecord (
    Id BIGINT,
    StudentName STRING,
    RegistrationTime TIMESTAMP(3),
    WATERMARK FOR RegistrationTime AS RegistrationTime - INTERVAL '3' MINUTE
) WITH ( ... ... );

WATERMARK FOR 某个Rowtime类型的列名 AS 某个Rowtime类型的列名

WATERMARK FOR my_time AS my_time

WATERMARK FOR 某个Rowtime类型的列名 AS 某个Rowtime类型的列名 - INTERVAL '时间长度' 时间单位

WATERMARK FOR my_time AS my_time - INTERVAL '3' SECOND

CREATE TABLE A (
    Id BIGINT,
    StudentName STRING,
    RegistrationTime TIMESTAMP(3)
) WITH ( ... 某些参数 ... );

CREATE TABLE B (
    WATERMARK FOR RegistrationTime AS RegistrationTime - INTERVAL '3' MINUTE
) WITH ( ... 另一些参数 ... ) LIKE `A`;