postgresql-9.2

问题 SQLAlchemy supports creating partial indexes in postgresql. Is it possible to create a partial unique index through SQLAlchemy? Imagine a table/model as so: class ScheduledPayment(Base): invoice_id = Column(Integer) is_canceled = Column(Boolean, default=False) I'd like a unique index where there can be only one "active" ScheduledPayment for a given invoice. I can create this manually in postgres: CREATE UNIQUE INDEX only_one_active_invoice on scheduled_payment (invoice_id, is_canceled) where

问题 Do you know what the maximum number of columns that can be queried in Postgresql? I need to know this before I start my project. 回答1: According to About PostgreSQL it's "250 - 1600 depending on column types". See "Limits". The column types affect it because in PostgreSQL rows may be at most 8kb (one page) wide, they cannot span pages. Big values in columns are OK because TOAST handles that, but there's a limit to how many columns you can fit in that depends on how wide the un-TOASTed data

问题 DROP SCHEMA tmp CASCADE; CREATE SCHEMA tmp ; SET search_path=tmp; CREATE TABLE primes ( pos SERIAL NOT NULL PRIMARY KEY , val INTEGER NOT NULL , CONSTRAINT primes_alt UNIQUE (val) ); CREATE FUNCTION is_prime(_val INTEGER) RETURNS BOOLEAN AS $func$ DECLARE ret BOOLEAN ; BEGIN SELECT False INTO ret WHERE EXISTS (SELECT * FROM primes ex WHERE ex.val = $1 OR ( (ex.val * ex.val) <= $1 AND ($1 % ex.val) = 0 ) ); RETURN COALESCE(ret, True); END; $func$ LANGUAGE plpgsql STABLE; CREATE VIEW vw_prime

问题 Currently PostgreSQL 9.2.4 is provided in OSX Mavericks. I have used the provided PostgreSQL since running Lion Server. When I started using it I was using a password that I now realize is not very secure. I am having trouble finding the right command to do this. The user/role (I supposed) that is provided is _postgres. This is the password I would like to change. I attempted the command below but honestly I'm not sure what it is supposed to do. I thought that this would allow me to access

问题 I am new to postgres and I play around with data loading. Here is the table definition from postgres 9.2 spec: CREATE TABLE weather ( city varchar(80), temp_lo int, -- low temperature temp_hi int, -- high temperature prcp real, -- precipitation date date ); I prepared the following data file (weather.txt): San Francisco 43 57 0.0 '1994-11-29' Hayward 54 37 0.0 '1994-11-29' and ran the COPY command: COPY weather FROM '~aviad/postsgres/playground/weather.txt'; now, when I run select * from

问题 How to assign default value to following type of Oracle statement into PostgreSQL 9.3? CREATE OR REPLACE FUNCTION(.... ... DECLARE v_var Table01.column01%TYPE := 'SLOW'; BEGIN ... ... END; 回答1: Postgres allows to provide parameter defaults , which kick in for missing parameters in the function call. Only allowed for parameters at the end of the list . Example: CREATE OR REPLACE FUNCTION foo ( param1 int , v_char tbl01.col01%TYPE DEFAULT 'foo' ) ... -- no need to DECLARE anything else. BEGIN .

问题 I'm setting up my local postgresql database for a rails project (that I'm joining), and have done the following: Installed postgres Added/bundled 'pg' gem Created a db user named "foobar" Created a db named "foobar_development" The rails app comes with a rake db:migrate task. When I run this task, I get the following error output: FATAL: no pg_hba.conf entry for host "::1", user "foobar", database "foobar_development", SSL off I found a pg_hba.conf file in the following location: /usr/local

问题 Hello i have got 4 tables first table is menu have got column: Id number PK parent_id number FK to menu.Id title character varying(250) softdel boolean default false second table is page : id as PK menu_id as FK to menu.id page_id as FK to page.id softdel boolean default false third table is article : id as PK and FK to page.id softdel boolean default set to false and fourth table article_lang : partial_id as PK id as FK to article.id language character softdel boolean default set to false

问题 I am working on PostgreSQL 9.2 and i want to create a table with capital letter without using double quotes.Is it possible by any how? means CREATE TABLE STUDENT(NAME VARCHAR(50)); i want the table name must be look like "STUDENT" But postgresql automatically convert it into "student". So is there any way exist to disable sensitive property of postgresql for column and table names? thank you. 来源： https://stackoverflow.com/questions/23217205/is-it-possible-to-create-insensitive-table-and

问题 OS 10.8.4, Python 2.7, PostgreSQL 9.2 I've been spending the past 10+ hours trying to get Psycopg2 installed for Django and am now receiving warnings and a failure that Google can't seem to help me with: After cleaning out all existing Psycopg2 & PostgreSQL files, reinstalling PostgreSQL 9.2 and Python 2.7, I was still getting the _PQbackendPID error when trying to install Psycopg2 with Pip. So I tried changing the ARCHFLAGS setting on install: $ sudo env ARCHFLAGS="-arch i386 -arch x86_64"