More Git Stuff

When first creating a branch, it’s best to push the branch immediately to the remote. This is because the first push of a new branch must include the flag -u to tell git to track the upstream branch. If you forget, it complicates stuff later.

So do a git push -u right after first creating a branch

Create branch

git checkout -b new-branch

Commit to new-branch with no changes (i.e. - “empty”) commit

git commit --allow-empty -m "Initial commit"

Now push with the -u flag (upstream)

git push -u origin new-branch

Now, it’s all good to go.

PostgreSQL

When changes are made to the models

Generate a new migration

alembic revision --autogenerate -m "Description of your changes"

Apply the migration

alembic upgrade head

To get into database with password

psql -U bread_user -d bread_db -h localhost

psql -U user_name -d databasename_db -h localhost

Common PostgreSQL Commands (Terminal/psql)

To switch to superuser from linux command line

sudo -u postgres psql

Basic Connection and Navigation:

psql: Opens the psql interactive terminal (default connection).
psql -U <username> -d <database_name>: Connect to a specific database as a user.
psql -h <hostname> -p <port> -U <username> -d <database_name>: Connect to a remote server.
\q or \quit: Exit psql.
\l or \list: List databases.
\c <database_name> or \connect <database_name>: Connect to a database.
\dt: List tables.
\dv: List views.
\df: List functions.
\du: List users (roles).
\h: Help for SQL commands.
\?: Help for psql meta-commands.
\e: Open query in editor.
\s: Display query history.
\timing: Toggle query timing.

Data Manipulation and Queries:

Don’t forget a semi-colon (;) at the end of the line/command
SELECT * FROM <table_name>;: Retrieve all data.
SELECT column1, column2 FROM <table_name> WHERE condition;: Retrieve specific columns.
INSERT INTO <table_name> (column1, column2) VALUES (value1, value2);: Insert data.
UPDATE <table_name> SET column1 = value1 WHERE condition;: Update data.
DELETE FROM <table_name> WHERE condition;: Delete data.
CREATE TABLE <table_name> (column1 type, column2 type, ...);: Create a table.
DROP TABLE <table_name>;: Delete a table.
ALTER TABLE <table_name> ADD COLUMN column3 type;: Add a column.
ALTER TABLE <table_name> DROP COLUMN column3;: Delete a column.
CREATE INDEX index_name ON table_name (column_name);: Create an index.
EXPLAIN SELECT * FROM table_name WHERE condition;: Show query plan.
BEGIN; ... COMMIT;: Start and commit a transaction.
BEGIN; ... ROLLBACK;: Start and rollback a transaction.

User and Role Management:

CREATE USER <username> WITH PASSWORD '<password>';: Create a user.
ALTER USER <username> WITH PASSWORD '<new_password>';: Change user password.
DROP USER <username>;: Delete a user.
GRANT <privilege> ON <object> TO <user/role>;: Grant privileges.
REVOKE <privilege> ON <object> FROM <user/role>;: Revoke privileges.
CREATE ROLE <role_name> WITH LOGIN;: create a role that can login.
GRANT <role_name> to <user_name>;: Grants a role to a user.

Database Management:

CREATE DATABASE <database_name>;: Create a database.
DROP DATABASE <database_name>;: Delete a database.
\set AUTOCOMMIT off: Disable autocommit.
\set AUTOCOMMIT on: Enable autocommit.

React

Rebuild frontend changes

cd ~/projects/bread/frontend

npm run build

Remove old files (optional, but recommended)

sudo rm -rf /var/www/recipes/html/*

Copy new files

sudo cp -r dist/* /var/www/recipes/html/

Set permissions

sudo chown -R www-data:www-data /var/www/recipes/html/

sudo chmod -R 755 /var/www/recipes/html/

Restarting Server

Kill any existing uvicorn processes

pkill -f uvicorn

Start uvicorn with explicit host binding

cd ~/projects/bread/backend

source venv/bin/activate

nohup uvicorn app.main:app --host 127.0.0.1 --port 8000 --forwarded-allow-ips='*' &

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