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78 lines
1.1 KiB
78 lines
1.1 KiB
# Python + SQL
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## Lessons
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1. Install a Python virtual environment
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1. Install psychopg2-binary
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1. Connect to Postgres via Python
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1. Running Queries with Python
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1. Migrating data to a SQLite
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1. Exporting data to CSV
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## Install a Python virtual environment
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```
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python3 -m venv ~/my-env
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source ~/my-env/bin/activate
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```
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## Install psychopg2-binary
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```
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python -m pip install psycopg2-binary
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```
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## Connect to Postgres via Python
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```python
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import psycopg2
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conn = psycopg2.connect(
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database="my_db"
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)
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# close connection
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conn.close()
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```
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## Running Queries with Python
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Select many
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```python
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cursor = conn.cursor()
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cursor.execute("SELECT * FROM people")
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print(cursor.fetchall())
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# close connection
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cursor.close()
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```
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Select one
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```ptyon
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cursor.execute("SELECT * FROM people WHERE id = 12")
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print(cursor.fetchone())
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```
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Insert
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```python
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cursor.execute("INSERT INTO people (name, age) VALUES (%s, %s)", ['Matt', 43])
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conn.commit()
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```
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Delete
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```python
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cursor.execute("DELETE FROM people WHERE id = 12");
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conn.commit()
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```
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Update
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```python
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cursor.execute("UPDATE people SET name = %s, age = %s WHERE id = %s", ['Matt', 43, 20])
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conn.commit()
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```
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