Question

我的postgresql-9.3.4（CentOS 6.5版）中有我自己的User Defined-Type名为MYUDT的运算符类

CREATE OPERATOR = (
    LEFTARG    = MYUDT,
    RIGHTARG   = MYUDT,
    PROCEDURE  = MYUDT_eq,
    NEGATOR    = <>,
    COMMUTATOR = =,
    JOIN       = eqjoinsel,
    HASHES,
    MERGES
);

CREATE OPERATOR CLASS MYUDT_OPS
DEFAULT FOR TYPE MYUDT USING BTREE AS
OPERATOR 1 <,
OPERATOR 2 <=,
OPERATOR 3 =,
OPERATOR 4 >=,
OPERATOR 5 >,
FUNCTION 1 MYUDT_OUT_CMP(MYUDT, MYUDT);

我有两个MYUDT表，其中已创建了B-Tree索引。

CREATE TABLE MY_TABLE1(C1 MYUDT, C2 VARCHAR(10));
CREATE INDEX IDX_MYUDT ON MY_TABLE1(C1);
CREATE TABLE MY_TABLE2(C1 MYUDT, C2 VARCHAR(10));

<，<=，>，>=，=，<>所需的运算符和函数都在那里，它可以正常运行nested Loop / Sort Merge加入，Hash join不起作用。

EXPLAIN SELECT * FROM MY_TABLE1 A, MY_TABLE2 B WHERE A.C1=B.C1;
                                         QUERY PLAN                                          
---------------------------------------------------------------------------------------------
 Hash Join  (cost=10000000012.30..10000000026.38 rows=9 width=500)
   Hash Cond: (b.C1= a.C1)
   ->  Seq Scan on MY_TABLE2 b  (cost=10000000000.00..10000000012.90 rows=290 width=250)
   ->  Hash  (cost=12.22..12.22 rows=6 width=250)
         ->  Index Scan using IDX_MYUDT on MY_TABLE1 a  (cost=0.13..12.22 rows=6 width=250)
(5 rows)

SELECT * FROM MY_TABLE1 A, MY_TABLE2 B WHERE A.C1=B.C1;
ERROR:  could not find hash function for hash operator 610980

我听说它需要创建hash operator class并且我这样做了。

CREATE FUNCTION MYUDT_hash(MYUDT)
RETURNS int LANGUAGE internal AS 'hashtext' IMMUTABLE;

CREATE OPERATOR CLASS MYUDT_HASH_OPS
DEFAULT FOR TYPE MYUDT USING hash AS
FUNCTION 1 MYUDT_hash(aria128);

但它仍然不起作用，我需要这个。我错过了什么？任何建议都将非常感激。

＆＃34;找不到散列运算符的散列函数＆＃34;在我的USER DEFINED-TYPE中

0 个答案: