Supplement: How to determine the path of the psql configuration file
①Switch to the psql user, here is thunisoft.
② There are many ways to determine the path, here are some commonly use
Month: September 2021
NOSQL – Use the relational database to carry out countless data – best practice
After reading the article written by Bret Taylor (Co-founder of FriendFeed, current CTO of Facebook) How FriendFeed uses MySQL to store schema-less data After the shocking article, I began to doubt
Find loop references in the PostgreSQL table?
I have a property sheet (ID int,SourceID int,TargetID int,TargetType int)
ID SourceID TargetID< br />———————
1 123 456
2 456 789
3 1 123
4 456 1
5 2 1
I want to find all circular references. I want to write a PL/pgsql function for this.
here ID 4 = 456 1 123 456 circular reference
Recursive JSON in PostgreSQL
I have the following table in PostgreSQL 9.5 server:
It is worth noting that the position is theoretically infinitely recursive. I need to generate a JSON message from the root position and r
PostgreSQL – HIVE flow does not work
I try to follow https://cwiki.apache.org/confluence/display/Hive/Streaming+Data+Ingest#StreamingDataIngest-StreamingRequirements to enable hive streaming I have changed all configuration properties
NOSQL Database Redis Series (1) – Introduction to Redis
I. Introduction to redis (1) Introduction to Redis
Redis is completely open source and free, complies with the BSD protocol, and is a high-performance key-value database.
Redis and othe
PowerDesigner Connect the mysql database using the DSN file
First create a new PDM model
Enter the password and click OK, there will be a little pause and then a pop-up will pop up. The connection is successful. This is to test whether it can be connected.
To connect to mysql in PDM, see the following steps:
PostgreSQL – Sharing routine in user community
I built a toolbox for a branch of biology. One of the reasons for choosing Julia is its simplicity, because biologists are not considered capable of writing complex C code
What I want to add is a
PostgreSQL – JSON WHERE uses Query Builder to CLAUSE
This is the JSON value in the data column of a thing table:
{a: [{b: 1} , {b: 2}]} I can use the original query like this to get all the content containing b equal to 1:
select * from t
PowerDesigner database
Novice learning database (1) Design the database with Powerdesigner
Description:
1. To learn to use development language for database programming, the key is to learn sql language, develo