postgresql-9.5

问题 I'm running Postgres 9.5 and am playing around with BRIN indexes. I have a fact table with about 150 million rows and I'm trying to get PG to use a BRIN index. My query is: select sum(transaction_amt), sum (total_amt) from fact_transaction where transaction_date_key between 20170101 and 20170201 I created both a BTREE index and a BRIN index (default pages_per_range value of 128) on column transaction_date_key (the above query is referring to January to February 2017). I would have thought

问题 This question can be considered as a follow-up on my comment on Can two concurrent but identical DELETE statements cause a deadlock?. I am wondering if the rows are locked in ascending my_status order in the following statement: SELECT 1 FROM my_table ORDER BY my_status FOR UPDATE; There is an interesting remark on https://www.postgresql.org/docs/9.5/static/sql-select.html which says: It is possible for a SELECT command running at the READ COMMITTED transaction isolation level and using ORDER

问题 This question can be considered as a follow-up on my comment on Can two concurrent but identical DELETE statements cause a deadlock?. I am wondering if the rows are locked in ascending my_status order in the following statement: SELECT 1 FROM my_table ORDER BY my_status FOR UPDATE; There is an interesting remark on https://www.postgresql.org/docs/9.5/static/sql-select.html which says: It is possible for a SELECT command running at the READ COMMITTED transaction isolation level and using ORDER

问题 This question can be considered as a follow-up on my comment on Can two concurrent but identical DELETE statements cause a deadlock?. I am wondering if the rows are locked in ascending my_status order in the following statement: SELECT 1 FROM my_table ORDER BY my_status FOR UPDATE; There is an interesting remark on https://www.postgresql.org/docs/9.5/static/sql-select.html which says: It is possible for a SELECT command running at the READ COMMITTED transaction isolation level and using ORDER

问题 When you are upserting a row (PostgreSQL >= 9.5), and you want the possible INSERT to be exactly the same as the possible UPDATE, you can write it like this: INSERT INTO tablename (id, username, password, level, email) VALUES (1, 'John', 'qwerty', 5, 'john@mail.com') ON CONFLICT (id) DO UPDATE SET id=EXCLUDED.id, username=EXCLUDED.username, password=EXCLUDED.password, level=EXCLUDED.level,email=EXCLUDED.email Is there a shorter way? To just say: use all the EXCLUDE values. In SQLite I used to

问题 Whenever I try to drop database I get: ERROR: database "pilot" is being accessed by other users DETAIL: There is 1 other session using the database. When I use: SELECT pg_terminate_backend(pg_stat_activity.pid) FROM pg_stat_activity WHERE pg_stat_activity.datname = 'TARGET_DB'; I terminated the connection from that DB, but if I try to drop database after that somehow someone automatically connects to that database and gives this error. What could be doing that? No one uses this database,

问题 PostgreSQL version: 9.5.4 I have a table defined as: CREATE TABLE IF NOT EXISTS TEST_1 ( ID SERIAL PRIMARY KEY, C1 BYTEA, C2 TEXT NOT NULL, C3 BOOLEAN NOT NULL DEFAULT FALSE, CONSTRAINT TEST_1_unique_idx UNIQUE(C1, C2) ); I have a view defined as: create or replace view test as select * from test_1 with cascaded check option; This is necessary to abstract from table name while application code is working via view name (to implement a kind of simple partitioning with replacing tables when

问题 In MySQL SELECT y, m, Count(users.created_date) FROM ( SELECT y, m FROM (SELECT YEAR(CURDATE()) y UNION ALL SELECT YEAR(CURDATE())-1) years, (SELECT 1 m UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9 UNION ALL SELECT 10 UNION ALL SELECT 11 UNION ALL SELECT 12) months) ym LEFT JOIN users ON ym.y = YEAR(FROM_UNIXTIME(users.created_date)) AND ym.m = MONTH(FROM_UNIXTIME(users.created_date))

问题 I have installed Postgresql@9.5 to my OSX El Capitan Machine using Homebrew 1.2. Unfortunately, upon installing Postgis, and performing CREATE EXTENSION postgis; It returns, ERROR: could not open extension control file "/usr/local/Cellar/postgresql@9.5/9.5.6/share/postgresql@9.5/extension/postgis.control": No such file or directory I tried, uninstalling all postgresql and install only the 9.5 version, and then installing postgis but to no avail. I think I got a similar question but this one

问题 Try as I might, I have not succeeded in installing the plpython3u extension on a PostgreSQL 9.5 x64 install. PostgreSQL 9.5 installed from pgdg repo: [joe@postgresql ~]$ yum list installed | grep pgdg CGAL.x86_64 4.7-1.rhel7 @pgdg95 SFCGAL.x86_64 1.2.2-1.rhel7 @pgdg95 SFCGAL-libs.x86_64 1.2.2-1.rhel7 @pgdg95 geos.x86_64 3.5.0-1.rhel7 @pgdg95 pgdg-centos95.noarch 9.5-2 installed plv8_95.x86_64 1.4.4-1.rhel7 @pgdg95 postgis2_95.x86_64 2.2.2-1.rhel7 @pgdg95 postgis2_95-client.x86_64 2.2.2-1