postgresql

问题 What I'm trying to set up: Cloud SQL instance with private IP, Postgresql database A VM with one public IP and one private IP on same VPC network as the SQL instance is on (VM, SQL instance and VPC are all in the same region) VM has a service account with sufficient Cloud SQL client/viewer permissions SQL proxy on VM connecting to SQL instance. I run it with the -ip_address_types=PRIVATE argument I've found in some of the documentation. Configuration code Slightly simplified Terraform code

问题 I see SELECT EXISTS used a lot like: if db.query(""" SELECT EXISTS ( SELECT 1 FROM checkout WHERE checkout_id = %s ) """ % checkout_id).getresult()[0][0] == 't': vs. what i prefer: if db.query(""" SELECT 1 FROM checkout WHERE checkout_id = %s LIMIT 1 """ % checkout_id).getresult(): Which one is preferred and why? P.S. i am using Python and PosgreSQL. cert=> explain SELECT EXISTS (SELECT 1 FROM checkout WHERE checkout_id = 3); QUERY PLAN --------------------------------------------------------

问题 I see SELECT EXISTS used a lot like: if db.query(""" SELECT EXISTS ( SELECT 1 FROM checkout WHERE checkout_id = %s ) """ % checkout_id).getresult()[0][0] == 't': vs. what i prefer: if db.query(""" SELECT 1 FROM checkout WHERE checkout_id = %s LIMIT 1 """ % checkout_id).getresult(): Which one is preferred and why? P.S. i am using Python and PosgreSQL. cert=> explain SELECT EXISTS (SELECT 1 FROM checkout WHERE checkout_id = 3); QUERY PLAN --------------------------------------------------------

问题 In a Postgres 9.3 database I have a table in which one column contains JSON, as in the test table shown in the example below. test=# create table things (id serial PRIMARY KEY, details json, other_field text); CREATE TABLE test=# \d things Table "public.things" Column | Type | Modifiers -------------+---------+----------------------------------------------------- id | integer | not null default nextval('things_id_seq'::regclass) details | json | other_field | text | Indexes: "things_pkey"

问题 I have the following model... type User struct { ID string `sql:"type:uuid;primary_key;default:uuid_generate_v4()"` FirstName string `form:"first_name" json:"first_name,omitempty"` LastName string `form:"last_name" json:"last_name,omitempty"` Password string `form:"password" json:"password" bindind:"required"` Email string `gorm:"type:varchar(110);unique_index" form:"email" json:"email,omitempty" binding:"required"` Location string `form:"location" json:"location,omitempty"` Avatar string

问题 What is the proper way to convert any text (or varchar) to jsonB type in Postgres (version 9.6) ? For example, here I am using two methods and I am getting different results: Method 1: dev=# select '[{"field":15,"operator":0,"value":"1"},{"field":15,"operator":0,"value":"2"},55]'::jsonb; jsonb ---------------------------------------------------------------------------------------------- [{"field": 15, "value": "1", "operator": 0}, {"field": 15, "value": "2", "operator": 0}, 55] (1 row) Method

问题 in my spring boot / hibernate application, I need to connect to a Postgres database "ax2012_1", which belong to the "dbo" schema. I have the following application.properties: # Database db.driver: org.postgresql.Driver db.url: jdbc:postgresql://localhost:5432/ax2012_1 db.username: my_user_name db.password: my_password spring.datasource.url= jdbc:postgresql://localhost:5432/ax2012_1 spring.datasource.username=my_user_name spring.datasource.password=my_password spring.datasource.schema=dbo

问题 in my spring boot / hibernate application, I need to connect to a Postgres database "ax2012_1", which belong to the "dbo" schema. I have the following application.properties: # Database db.driver: org.postgresql.Driver db.url: jdbc:postgresql://localhost:5432/ax2012_1 db.username: my_user_name db.password: my_password spring.datasource.url= jdbc:postgresql://localhost:5432/ax2012_1 spring.datasource.username=my_user_name spring.datasource.password=my_password spring.datasource.schema=dbo

问题 I'm trying to convert minutes which are in integer to interval in postgres Is their any function that will help me to convert it to interval or should i have divide it by 60 and get the final result 20 minutes will be like 00:20:00 as result 回答1: Fastest way is with make_interval make_interval(years int DEFAULT 0, months int DEFAULT 0, weeks int DEFAULT 0, days int DEFAULT 0, hours int DEFAULT 0, mins int DEFAULT 0, secs double precision DEFAULT 0.0) So it looks like this (as suggested by

问题 I am looking for a basic script/command that will create a copy of a live database (let name them mydb and mydb_test , both on the same server). Requirements it has to run even if the mydb_test already exists and have records it has to work even if mydb and mydb_test do have existing connections it have to clean the potentially existing database if necessary Hints: drop database cannot be used if you have existing connections 回答1: The simplest and fastest method to create a complete copy of