postgres 按日分表

 CREATE OR REPLACE FUNCTION auto_insert_into_tbl_partition()
  RETURNS trigger AS
$BODY$
DECLARE
    time_column_name     text ;        -- 时间字段，用时间判断日期以此分表，属于必填的
    curMMDD         varchar(16);    -- ‘YYYYMMDD‘格式的字串,用做分区子表的后缀
    isExist         boolean;        -- 判断分区子表是否已存在
    strSQL          text;
    
BEGIN
    -- 从调用参数中获取time_column_name
    time_column_name := TG_ARGV[0];
   
    -- 判断对应分区表是否已经存在
    EXECUTE ‘SELECT $1.‘||time_column_name INTO strSQL USING NEW;
    curMMDD := to_char(strSQL::timestamp,‘YYYYMMDD‘);
    select count(1) INTO isExist from pg_class where relname = (‘t_audit_‘||curMMDD);
 
    -- 若不存在先创建子分区再插入
    IF (isExist = false) THEN  
        -- 创建子分区表继承父表
        strSQL := ‘CREATE TABLE IF NOT EXISTS t_audit_‘||curMMDD||‘() INHERITS (t_audit);‘;  
        EXECUTE strSQL;
        -- 创建索引
        strSQL := ‘CREATE INDEX t_audit_‘||curMMDD||‘_INDEX_‘||time_column_name||‘ ON t_audit_‘||curMMDD||‘ (‘||time_column_name||‘);‘ ;
        EXECUTE strSQL;
    END IF;
 
    -- 插入数据到子分区!
    strSQL := ‘INSERT INTO t_audit_‘||curMMDD||‘ SELECT $1.*‘;
    EXECUTE strSQL USING NEW;
    RETURN NULL; 
END
$BODY$
LANGUAGE plpgsql;
 

-- 创建触发器，insert操作时触发
CREATE TRIGGER insert_tbl_partition_trigger
  BEFORE INSERT
  ON t_audit
  FOR EACH ROW
  EXECUTE PROCEDURE auto_insert_into_tbl_partition(‘time‘);