CREATE OPERATOR name (
PROCEDURE = funcname
[, LEFTARG = lefttype ] [, RIGHTARG = righttype ]
[, COMMUTATOR = com_op ] [, NEGATOR = neg_op ]
[, RESTRICT = res_proc ] [, JOIN = join_proc ]
[, HASHES ] [, MERGES ]
[, SORT1 = left_sort_op ] [, SORT2 = right_sort_op ]
[, LTCMP = less_than_op ] [, GTCMP = greater_than_op ]
)
CREATE OPERATOR 垔幬婔婻桄䔇 name 淉嘩严㔗垔幬臖淉嘩严䔇䫘潙儖潊婺噽欔橬蔙㔗套悩䂍庺庖婔婻昇嚟劉闼幽臖淉嘩严儖婘毺垔䔇昇嚟婺录傺㔗劥彍垄嚔婘嘷嬉昇嚟婺录傺㔗
淉嘩严 name 滇婔婻橔崔 NAMEDATALEN-1 阪䔇(䚺䩕婺 63 婻)婋彖庖严䂇潊䔇庖严婾
+ - * / < > = ~ ! @ # % ^ & | ` ?
嘹锬拷劉庖䔇施唍橬庹婻鍊彽-- 启 /* 婉脘婘淉嘩严䔇傂嘘婄桹庺䯄啹婺垄傸嚔赆螴婺滇婔婻濘麪䔇嚔哋㔗
婔婻崔庖严䔇淉嘩严婉脘傖 + 潡 - 䂷儆鍴麂臖劉庖誻寙劆躿儏婋麵庖严幋婔
~ ! @ # % ^ & | ` ?
冋套 @- 滇婔婻噕螩䔇淉嘩严劉嘖 *- 婉滇㔗認婻鍊彽噕螩 PostgreSQL 彖悊 SQL 噚垹䔇昖臵蔯婉襕挗婘严埙幋閘橬䷺䍘㔗淉嘩严 != 婘膷噖施滹儇潊 <> 啹溴認婴婻劉䓄攂滇京備䔇㔗
躿儏驔襕垔幬婔婻 LEFTARG 启 RIGHTARG 㔗凹庯埯䕞淉嘩严準臘婴蔙鄘驔襕垔幬㔗凹埿䕞淉嘩严準臘埻驔襕垔幬 LEFTARG 蔯凹庯噥䕞淉嘩严準臘埻驔襕垔幬 RIGHTARG 㔗
劯湙funcname 誺䘋媙釂噾䂟䫘 CREATE FUNCTION 垔幬誺蔯婫媙釂垔幬婺毖埖溼䇞昄麟䔇毺垔䌂傋埗昄(婔婻潡滇婴婻)㔗
噽垄床埖弄滯埇锬䔇淉嘩严嚻寡床埖㔗傡傸䔇劆幬婘誗33.13麯垔幬㔗
襕垔幬䔇淉嘩严㔗埇䫘䔇庖严蓕婪桺㔗噽劉庖埇傖䫘昇嚟媞閄(懫套 CREATE OPERATOR myschema.+ (...))㔗套悩澇橬昇嚟彍婘嘷嬉昇嚟婺录傺淉嘩严㔗劯婔婻昇嚟婺䔇婴婻淉嘩严埇傖橬婔湙䔇劉庖埻襕傡傸淉嘩婉劯䔇昄扞䌂傋㔗認埆啔麉蘘㔗
䫘庯垂䯄臖淉嘩严䔇庘昄
淉嘩严噥膹䔇埗昄昄扞䌂傋套悩庻婘䔇臺㔗套悩滇噥䕞淉嘩严認婻埗昄埇傖䩕䘖㔗
淉嘩严埿膹䔇埗昄昄扞䌂傋套悩庻婘䔇臺㔗套悩滇埿䕞淉嘩严認婻埗昄埇傖䩕䘖㔗
臖淉嘩严凹庫䔇庴扵淉嘩严
臖淉嘩严凹庫䔇蘘淉嘩严
溴淉嘩严亥溘锬拷攓臇嚄庘昄
溴淉嘩严誂毖锬拷攓臇嚄庘昄
臘滯溴淉嘩严櫇毕 Hash 誂毖
臘滯溴淉嘩严埇傖櫇毕婔婻肉劽誂毖
溴淉嘩严䔇噥膹昄扞䔇毐废淉嘩严(套悩溴淉嘩严櫇毕肉劽誂毖)
溴淉嘩严䔇埿膹昄扞䔇毐废淉嘩严(套悩溴淉嘩严櫇毕肉劽誂毖)
懫膄認婻淉嘩严䔇膷噖昄扞䌂傋䔇償庯淉嘩严(套悩溴淉嘩严櫇毕肉劽誂毖)
懫膄認婻淉嘩严䔇膷噖昄扞䌂傋䔇崓庯淉嘩严(套悩溴淉嘩严櫇毕肉劽誂毖)
嘪䫘 OPERATOR() 臺濘婘 com_op 潡蔙噽垄埇锬埗昄麯䂍庺婔婻昇嚟媞閄䔇淉嘩严劉懫套
COMMUTATOR = OPERATOR(myschema.===) ,
婋麵变傴垔幬婔婻桄淉嘩严麵䓇䕩京䫘庯 box 昄扞䌂傋㔗
CREATE OPERATOR === (
LEFTARG = box,
RIGHTARG = box,
PROCEDURE = area_equal_procedure,
COMMUTATOR = ===,
NEGATOR = !==,
RESTRICT = area_restriction_procedure,
JOIN = area_join_procedure,
HASHES,
SORT1 = <<<,
SORT2 = <<<
-- 啹婺䂍庺庖毐废淉嘩严欔傖䘵嚘锊劆婄橬 MERGES 㔗
-- LTCMP 启 GTCMP 彖彆啺螆滇 < 启 >
);