postgresql-9.1

问题 When running the rake db:structure:dump command, I encountered the following error: Larson-2:app larson$ rake db:structure:dump pg_dump: server version: 9.1.3; pg_dump version: 9.0.4 pg_dump: aborting because of server version mismatch rake aborted! Error dumping database How can I go about updating pg_dump? I have pg 9.1.3 installed, is there a way to update the references inside of Rails to the new version? When I try to update postgres via homebrew, I get the following output: Larson-2:app

问题 I have a query string generated in a postgres UDF, i'd like to put it's result in a temp table to perform joins against (I'm using LIMIT and OFFSET , and I don't want to join against other ttables only to end up choping the data off at the end --i.e., the LIMIT operator in the query plan). I attempt to create the temp table with the following statement. CREATE LOCAL TEMP TABLE query_result ON COMMIT DROP AS EXECUTE query_string_; But I get the following error notice : ********** Error *******

问题 This question already has an answer here : How to create a new database with the hstore extension already installed? (1 answer) Closed 6 years ago . I set up a Rails app on a remote server and created an hstore extension sudo -u postgres psql CREATE EXTENSION hstore; I then deployed an iteration of the app that uses hstore in one of the postgres tables, but when it ran the migrations it gave an error message PG::UndefinedObject: ERROR: type "hstore" does not exist I then tried to do this

问题 I get the following errors in airbrake if my staging (2 servers) or production (4 servers) servers have no activity for about 15 minutes. Here are the error messages: ActiveRecord::StatementInvalid: PG::Error: could not receive data from server: Connection timed out OR PG::Error: could not connect to server: Connection timed out Is the server running on host "tci-db4.dev.prod" and accepting TCP/IP connections on port 5432? I'm using PostgreSQL as my database. One of the servers also acts as

问题 I have a model Task t.string "name" t.hstore "actions" Example: #<Task id: 1, name: "first", actions: {"today"=>"9"}, #<Task id: 2, name: "second", actions: {"yesterday"=>"1"}, #<Task id: 3, name: "third", actions: nil, #<Task id: 4, name: "four", actions: {"today"=>"11"}, I need to find all records where actions: nil, :today<10 and key :today not present. It is 1,2,3 task. Task.where("actions -> 'today' < '10'") - it return only first task. Task.where("actions -> 'today' < '10' OR actions IS

问题 I am using Ubuntu 12.10 64-bit and I have following packages installed : dpkg --get-selections | grep postgre output: postgresql postgresql-9.1 postgresql-client postgresql-client-9.1 postgresql-client-common postgresql-common postgresql-contrib postgresql-contrib-9.1 postgresql-server-dev-9.1 postgresql-server-dev-all libpq-dev libpq5 rvm 1.17.9 ruby 1.9.3p362 (2012-12-25 revision 38607) [x86_64-linux] I am not able to install pg gem I am getting following error : ERROR: Error installing pg:

问题 I am representing a graph in Postgres 9.1 (happens to be bidirectional and cyclic): CREATE TABLE nodes ( id SERIAL PRIMARY KEY, name text ); CREATE TABLE edges ( id SERIAL PRIMARY KEY, node1_id int REFERENCES nodes(id), node2_id int REFERENCES nodes(id) ); Given a particular node ID, want to retrieve all other nodes in that cluster. I started with the "Paths from a single node" example here, and this is where I got: WITH RECURSIVE search_graph(id, path) AS ( SELECT id, ARRAY[id] FROM nodes

问题 I have been trying to find an optimal solution to select unique values from each column . My problem is I don't know column names in advance since different table has different number of columns. So first, I have to find column names and I could use below query to do it: select column_name from information_schema.columns where table_name='m0301010000_ds' and column_name like 'c%' Sample output for column names: c1, c2a, c2b, c2c, c2d, c2e, c2f, c2g, c2h, c2i, c2j, c2k, ... Then I would use

问题 This could be incredibly simple by the documentation is quite on it. Is there a way to aggregate columns via multiplication operator in postgresql. I know i can do count(column) or sum(column), but is there a multiply(column) or product(column) function that i can use. If not, any ideas how to achieve it. I'm using postgres 9.1 regards, Hassan 回答1: Sure, just define an aggregate over the base multiplication function. E.g. for bigint: CREATE AGGREGATE mul(bigint) ( SFUNC = int8mul, STYPE

问题 We convert time stamps to epoch, do some math on them and then convert them back to time stamps. All times in the database are TIMESTAMP WITHOUT TIME ZONE . Since the switch to summer time here in the UK times are off by one hour on one server but not on the other so I did a little test: SHOW SERVER_VERSION; SHOW TIMEZONE; SELECT extract(EPOCH FROM TIMESTAMP '1970-01-01'); On one server I get server_version ---------------- 9.1.15 (1 row) TimeZone ---------- GB (1 row) date_part ----------- 0