PyPQL Documentation

Introduction

PyPQL is a lightweight Python library that simplifies working with PostgreSQL. It is designed for projects that need easy CRUD operations with strong consistency but do not require the complexity of large-scale ORM frameworks.

Installation

pip install pypql

Quick Start

import asyncio
from pypql import tableobj

users = Table('user', 'password', 'database', 'host', 'table_name')
await users.connect()
await users.insert_single(['name'], ['Bobby']) # Inserts new row with value "Bobby" into name column of users table
await users.close()
      

API Overview

• Database class A class to manage an asynchronous connection to a PostgreSQL database using `asyncpg`.
  • Attributes:
    • _db_config (dict): Configuration for database connection containing user, password, database, & host.
    • connection (asyncpg.Connection): The active database connection or `None` if not connected.
  • Methods:
    • __init__(user, password, database, host): Initializes the database configuration with the given parameters.
      • user (str):The username for the database.
      • password (str): The password for the database.
      • database (str): The name of the database to connect to.
      • host (str): The hostname or IP address of the database server.
    • connect(): Establishes an asynchronous connection to the PostgreSQL database. Returns asyncpg.Connection.
    • close(): Closes the active database connection.
    • connection_info(): Returns information about the current connection state. Retrieves information about the current connection state (dict).
• Table class The Table class extends the `Database` clas to manage table-specific operations in a PostgreSQL database.
  • Attributes:
    • table_name (str): The name of the table the class interacts with.
  • Methods:
    • insert_single(columnNames, values): Inserts a single row into the table.
    • insert_multiple(columnNames, values): Inserts multiple rows into the table.
    • del_single(column, value): Deletes a single row based on a column-value pair.
    • del_multiple(column, values): Deletes multiple rows based on a column and a list of values.
    • del_custom(condition): Deletes rows based on a custom condition.
    • update(setColumn, newVal, conditionColumn, conditionVal): Updates rows based on a condition.
    • exc(func, *args): Executes a function with database connectivity management.
    • select(selection, returnMethod): Selects and returns data from the table with different return formats.
    • select_conditional(selection, condition, returnMethod): Selects and returns data from the table based on a condition.
    • customQuery(queryType, query): Executes a custom SQL query based on the type.
    • tableInfo(): Retrieves metadata about the table, including column names and row count.
• select_all() – Returns all rows.
• select_where(**kwargs) – Returns rows matching a condition.
• update(where: dict, values: dict) – Updates rows matching a condition.
• delete(**kwargs) – Deletes rows matching a condition.

Best Practices

• Always close connections when your app shuts down.
• Use transactions for bulk operations.
• Store your database URI in environment variables for production.