# sqlalchemy-trino

**Repository Path**: github_repo/sqlalchemy-trino

## Basic Information

- **Project Name**: sqlalchemy-trino
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2024-10-16
- **Last Updated**: 2024-10-16

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

sqlalchemy-trino
================

## ⚠️ Deprecation and Archive Notice
`sqlalchemy-trino` was developed as _[Trino](https://trino.io/) (f.k.a PrestoSQL) dialect for SQLAlchemy._
Since trinodb/trino-python-client#81, all code of `sqlalchemy-trino` is donated and merged into upstream project.
So now, this project is no longer active and consider as deprecated.


## Supported Trino version

Trino version 352 and higher

## Installation
The driver can either be installed through PyPi or from the source code.
### Through Python Package Index
```bash
pip install sqlalchemy-trino
```

### Latest from Source Code
```bash
pip install git+https://github.com/dungdm93/sqlalchemy-trino
```

## Usage
To connect from SQLAlchemy to Trino, use connection string (URL) following this pattern:
```
trino://<username>:<password>@<host>:<port>/catalog/[schema]
```

### JWT authentication

You can pass the JWT token via either `connect_args` or the query string
parameter `accessToken`:

```Python
from sqlalchemy.engine import create_engine
from trino.auth import JWTAuthentication

# pass access token via connect_args
engine = create_engine(
  'trino://<username>@<host>:<port>/',
  connect_args={'auth': JWTAuthentication('a-jwt-token')},
)

# pass access token via the query string param accessToken
engine = create_engine(
  'trino://<username>@<host>:<port>/?accessToken=a-jwt-token',
)
```

**Notice**: When using username and password, it will connect to Trino over TLS
connection automatically.

### User impersonation

It supports user impersonation with username and password based authentication only.

You can pass the session user (a.k.a., the user that will be impersonated) via
either [`connect_args`](https://docs.sqlalchemy.org/en/13/core/engines.html#sqlalchemy.create_engine.params.connect_args)
or the query string parameter `sessionUser`:

```Python
from sqlalchemy.engine import create_engine

# pass session user via connect_args
engine = create_engine(
  'trino://<username>:<password>@<host>:<port>/',
  connect_args={'user': 'user-to-be-impersonated'},
)

# pass session user via a query string parameter
engine = create_engine(
  'trino://<username>:<password>@<host>:<port>/?sessionUser=user-to-be-impersonated',
)
```

### Pandas support
```python
import pandas as pd
from pandas import DataFrame
import sqlalchemy_trino
from sqlalchemy.engine import Engine, Connection

def trino_pandas_write(engine: Engine):
    df: DataFrame = pd.read_csv("tests/data/population.csv")
    df.to_sql(con=engine, schema="default", name="abcxyz", method="multi", index=False)

    print(df)


def trino_pandas_read(engine: Engine):
    connection: Connection = engine.connect()
    df = pd.read_sql("SELECT * FROM public.foobar", connection)

    print(df)
```

**Note**: in `df.to_sql` following params is required:
* `index=False` because index is not supported in Trino.
* `method="multi"`: currently `method=None` (default) is not working because Trino dbapi is not support [`executemany`](https://github.com/trinodb/trino-python-client/blob/77adbc48cd5061b2c55e56225d67dd7822284b73/trino/dbapi.py#L410-L411) yet