PostgreSql Partition + Hibernate Insert

与Oracle不同。PostgreSQL须要手动控制分区规则触发器。

步骤一：创建分区

CREATE TABLE table_partition_1( CHECK partition_column criteria) INHENRITS (table)

步骤二：为分区表创建PK跟index，这里使用btree

ALTER TABLE ONLY table_partition_1
 ADD CONSTRAINT table_partition_1_pkey PRIMARY KEY (key_column);

CREATE INDEX index_table_partition_1 ON table_partition_1  USING btree(column);

步骤三：手动创建触发器

CREATE OR REPLACE FUNCTION before_insert_table()
  RETURNS trigger AS
$BODY$
 DECLARE
BEGIN
if criteria  then
	EXECUTE 'insert into appropriate table ...'  SELECT  ($1).* '  USING NEW;
end if;
return null;
END;
$BODY$
  LANGUAGE plpgsql VOLATILE
  COST 100;
ALTER FUNCTION before_insert_table()
  OWNER TO db;

rule在批量操作时更合适，可是对于单独操作会占用较大的开销。

CREATE RULE table_partition_1 _insert AS
(criteria ...)
DO INSTEAD
    INSERT INTO table_partition_1 VALUES (NEW.*)

步骤四：触发器方式hibernate向分区插入数据时。获得的result count为0，会导致推断失败而回滚。

解决方法是使用rule，或者声明分区插入时不进行result检查。

@SQLInsert(sql = "INSERT INTO "
		+ "table(column,...)"
		+ " VALUES(?,...)", check = ResultCheckStyle.NONE)

在Java项目中。考虑到分区创建会採用job方式自己主动创建，能够通过function完毕创建。

CREATE OR REPLACE FUNCTION "public"."function"()
  RETURNS void AS $BODY$
 DECLARE
 	 _tablename text ;
   quarter integer;
	record1 record;
BEGIN
	select function(now()) as quarter  into record1;
  quarter := record1.quarter;
	_tablename := 'partition_name';
PERFORM 1
FROM   pg_catalog.pg_class c
WHERE  c.relname = _tablename;
	IF FOUND <> TRUE THEN
			EXECUTE 'CREATE TABLE ' || _tablename  || ' (
        CHECK ( criteria)
     ) INHERITS (table)';
		EXECUTE 'ALTER TABLE ' || _tablename  || ' OWNER TO db ';
		EXECUTE  ' alter table ' ||   _tablename || ' add CONSTRAINT  ' || _tablename||'_pkey  PRIMARY key (column) ' ;
		EXECUTE  ' CREATE INDEX ' || _tablename|| '_index
		ON '||  _tablename ||'
		USING btree
		(column)';
  END IF;
END
$BODY$
  LANGUAGE 'plpgsql' VOLATILE COST 100;
ALTER FUNCTION "public"."function"() OWNER TO "db";

參考资料：

entity-hibspec-customsql.html

postgresql-table-partitioning-hibernate.html