Once we've installed `psychopg2-binary`, we can import it just like any other package that comes as part of the default Python installation.
To connect to the database, we need to run `psycopg2.connect()` and supply the correct data. To close the connection, run `conn.close()`
To connect to the database, we need to run `psycopg2.connect()` and supply the correct data. To close the connection, run `connection.close()`
```python
import psycopg2
conn = psycopg2.connect(
connection = psycopg2.connect(
database="my_db"
)
# close connection
conn.close()
connection.close()
```
## Running Queries with Python
@ -60,7 +60,7 @@ Running queries requires a "cursor" which is basically just something that perfo
Let's create a cursor and then have it perform a `SELECT` query. Once, the cursor has executed the query, it gives us a few functions that control have we view the data. Let's fetch all of the rows returned from the execution of the query and place them in a list. Note that each row is represented as a `tuple` is just an immutable list. When you're done, you'll need to close the cursor with `cursor.close()` in addition to closing the connection (shown above)
```python
cursor = conn.cursor()
cursor = connection.cursor()
cursor.execute("SELECT * FROM people")
print(cursor.fetchall())
@ -80,21 +80,21 @@ Now let's run an `INSERT` with two parameters passed in. The order of the `%s`
```python
cursor.execute("INSERT INTO people (name, age) VALUES (%s, %s)", ['Matt', 43])
conn.commit()
connection.commit()
```
Delete is pretty simple once we know the basics
```python
cursor.execute("DELETE FROM people WHERE id = %s", [24]);
conn.commit()
connection.commit()
```
Update is just more of the same, but make sure your array parameter matches the `%s` placeholders
```python
cursor.execute("UPDATE people SET name = %s, age = %s WHERE id = %s", ['Matt', 43, 20])
conn.commit()
connection.commit()
```
## SQLite Basics
@ -116,25 +116,25 @@ cursor = connection.cursor()
cursor.execute("CREATE TABLE people (name, age)")
```
Very similar, except that `cursor.execute` returns a result set that has the `fetchone`/`fetchall` functionality
`INSERT` is very similar to `psycopg2-binary`, but you use `?` instead of `%s`
```python
result = cursor.execute("SELECT * FROM people")
print(result.fetchall())
cursor.execute("INSERT INTO people (name, age) VALUES (?, ?)", ['Zagthorp', 543])
connection.commit()
```
Selecting a single row is similar to `psycopg2-binary`, but you use `?` instead of `%s`
Having the cursor execute a `SELECT` statement is very similar to `psycopg2-binary`, except that `cursor.execute` returns a result set that has the `fetchone`/`fetchall` functionality
```python
result = cursor.execute("SELECT * FROM people WHERE name = ?", ['Matt'])
print(result.fetchone())
result = cursor.execute("SELECT * FROM people")
print(result.fetchall())
```
`INSERT` works as expected
Selecting a single row works as expected
```python
cursor.execute("INSERT INTO people (name, age) VALUES (?, ?)", ['Zagthorp', 543])
connection.commit()
result = cursor.execute("SELECT * FROM people WHERE name = ?", ['Matt'])
