Postgresql gist index is not hit -


i using postgresql version 9.3.

i learned normal b-tree indexes can not used queries 'x%x%x' wildcards , find gist , gin indexes make wildcard queries hit index.

so decided use indexes , added btree-gist extension using command in postgresql;

create extension btree_gist;

after added gist index table , ;

create index ix_bras_interface_name on bras_interface using gist (name);

after added this, see added;

   table_name   |                index_name                 |    column_name ----------------+-------------------------------------------+-------------------  bras_interface | bras_interface_context_id                 | context_id  bras_interface | bras_interface_domain_id                  | domain_id  bras_interface | bras_interface_managed_object_id          | managed_object_id  bras_interface | bras_interface_name_59ec675d0b9537ac_uniq | context_id  bras_interface | bras_interface_name_59ec675d0b9537ac_uniq | name  bras_interface | bras_interface_name_idx                   | name  bras_interface | bras_interface_pkey                       | id  bras_interface | bras_interface_task_id                    | task_id  **bras_interface | ix_bras_interface_name                    | name** (9 rows)

but, simple query still not hit index. here simple query , analyser result;

my_user=# explain analyze select * bras_interface name '%my_text%';                                                  query plan -------------------------------------------------------------------------------------------------------------  seq scan on bras_interface  (cost=0.00..764.95 rows=1 width=1420) (actual time=5.589..5.589 rows=0 loops=1)    filter: ((name)::text ~~ '%my_text%'::text)    rows removed filter: 27596  total runtime: 5.613 ms (4 rows)

and see not hitting index. followed tutorials , couldn't see solution, problem. missing gist indexing?

like a_horse_with_no_name has said, you've picked wrong extension.

the btree_gist extension lets use index "distance" operator. lets have gist index spanning multiple columns 1 might e.g. tsearch vector , simple int.

the pg_trgm extension 1 match-anywhere-in-string indexing. aware it's quite expensive index though.


Comments

Post a Comment

Popular posts from this blog

android - Get AccessToken using signpost OAuth without opening a browser (Two legged Oauth) -

i using signpost oauth access data magento server. have read various tutorials on same , reach point open browser user can enter credentials. however, per requirement have automate part. hence, user should not browser page. have set-up done on server side ( magento ), hit url , returned call page. same through program in android. i have tried below, consumer = new commonshttpoauthconsumer(key, secret); provider = new commonshttpoauthprovider(oauth_init_url,access_token_url, authorize_url); try { provider.retrieverequesttoken(consumer, oauth.out_of_band); log.d("tokens" , consumer.gettoken() + " -- " + consumer.gettokensecret()); } and request tokens. dont know how bypass next step. tried directly accessing accesstoken (stupid of me) provider.retrieveaccesstoken(consumer, "mycallback://callback"); no luck, ends in oauth.signpost.exception.oauthnotauthorizedexception: authorization failed (server replied 401). ...
Read more

org.mockito.exceptions.misusing.InvalidUseOfMatchersException: mockito -

getting error org.mockito.exceptions.misusing.invaliduseofmatchersexception: invalid use of argument matchers! 1 matchers expected, 2 recorded. exception may occur if matchers combined raw values: //incorrect: somemethod(anyobject(), "raw string"); when using matchers, arguments have provided matchers. example: //correct: somemethod(anyobject(), eq("string matcher")); at when( getprogramservice .callservice(any(getprogramtype.class))) .thenreturn(jaxbresponse); please explain error , possible resolution the code posted looks fine; don't see problem it. code before or above causing exception. key here: invalid use of argument matchers! 1 matchers expected, 2 recorded. any , used above, doesn't return "special kind of null" or "special kind of getprogramtype"; don't exist. instead, returns null , side effect puts matcher on stack. whe...
Read more

google shop client API returns 400 bad request error while adding an item -

i'm working on solution add items in google shopping market java application. following tutorial real mess because of missing classes of laste release, after setting 1.5-beta maven managed make base example typecheck correctly classes. still can make simple task of adding 1 item. instead of posting whole code i'm posting part creates product feed. private product createproduct(string id) { product product = new product(); product.title = "red wool sweater"; product.content = new content( "text", "comfortable , soft, sweater keep warm on " + "cold winter nights. red , blue stripes."); product.appcontrol = new appcontrol(); product.appcontrol.addrequireddestination("productads"); product.externalid = id; product.lang = "it"; product.country = "it"; product.condition = "nuovo"; product.price = new price("eu...
Read more