Must read Get your database under version control. Check the series of posts by K. Scott Allen. When it comes to version control, the database is often a second or even third-class citizen. From what I’ve seen, teams that would never think of writing code without version control in a million years– and rightly so– … Read more
Had a similar problem; a pid file was blocking postgres from starting up. To fix it: $ rm /usr/local/var/postgres/postmaster.pid $ brew services restart postgresql and then all is well. UPDATE: For Apple M1 (Big Sur) users, do this instead: $ rm /opt/homebrew/var/postgres/postmaster.pid $ brew services restart postgresql
psql databasename < data_base_dump That’s the command you are looking for. Beware: databasename must be created before importing. Have a look at the PostgreSQL Docs Chapter 23. Backup and Restore.
you can change the encryption of the password like this. ALTER USER ‘yourusername’@’localhost’ IDENTIFIED WITH mysql_native_password BY ‘youpassword’;
If the database you want to restore doesn’t already exist, you need to create it first. On the command-line, if you’re in the same directory that contains the dumped file, use these commands (with appropriate substitutions): C:\> mysql -u root -p mysql> create database mydb; mysql> use mydb; mysql> source db_backup.dump;
There is a lot of confusion around this, I will try to make it as simple as possible. The primary key is a general concept to indicate one or more columns used to retrieve data from a Table. The primary key may be SIMPLE and even declared inline: create table stackoverflow_simple ( key text PRIMARY … Read more
You can use the –ignore-table option. So you could do mysqldump -u USERNAME -pPASSWORD DATABASE –ignore-table=DATABASE.table1 > database.sql There is no whitespace after -p (this is not a typo). To ignore multiple tables, use this option multiple times, this is documented to work since at least version 5.0. If you want an alternative way to … Read more
So what is this “require?” require() is not part of the standard JavaScript API. But in Node.js, it’s a built-in function with a special purpose: to load modules. Modules are a way to split an application into separate files instead of having all of your application in one file. This concept is also present in … Read more
don’t forget about transactions. Performance is good, but simple (IF EXISTS..) approach is very dangerous. When multiple threads will try to perform Insert-or-update you can easily get primary key violation. Solutions provided by @Beau Crawford & @Esteban show general idea but error-prone. To avoid deadlocks and PK violations you can use something like this: begin … Read more
db:migrate runs (single) migrations that have not run yet. db:create creates the database db:drop deletes the database db:schema:load creates tables and columns within the existing database following schema.rb. This will delete existing data. db:setup does db:create, db:schema:load, db:seed db:reset does db:drop, db:setup db:migrate:reset does db:drop, db:create, db:migrate Typically, you would use db:migrate after having made … Read more