joshlk/SQLAlchemy_quickstart.md

## SQLAlchemy_quickstart.md

      
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              SQLAlchemy_quickstart.md
            
          
    SQLAlchemy has two parts:
* ORM: this maps table and relationships between tables to Python objects
* Core: alows you to write and execute SQL using Python exspressions

Core

Select statment:
import pandas as pd
from sqlalchemy import select, cast, column, create_engine, Table, MetaData, insert

engine = create_engine("...")
metadata = MetaData(bind=engine, reflect=True)

table_X = metadata.tables['table_X']

sql = select([   # Dont use table_X.select() ass you cant specify columns
      table_X.columns('x')
    ]
).limit(10)

pd.read_sql_query(sql, engine)
To inspect an SQL statment:
str(sql) or print(sql)

To compile against SQL variant and include paramters:
print(select_i.compile(eng, compile_kwargs={"literal_binds": True}))

Other cheet sheet: https://www.pythonsheets.com/notes/python-sqlalchemy.html