Jerry Jerry - 1 year ago 85
Python Question

SqlAlchemy: export table to new database

Only recently started using python, and I like it! However, I am stuck with SqlAlchemy.

I am trying to write a script that reads an MS SQL database, query a table (all fields, only a filter on some fields), and write the results to a local SQLite database.

(The object is to write a data adapter: perform some queries on the SQLite database before exporting the results to another database. Writing to temporary table in the target database is also possible.)

I can make a connection and get query results - I can print them so I know that part works. But how can I create a new table based on the structure of the query results from the source SQL Server?

This works:

import sqlalchemy

esd = sqlalchemy.create_engine( 'mssql+pyodbc://username:passwordSservername/dbname' )
for row in esd.execute( 'select * from ticket_actions where log_dt > \'2012-09-01\''):
print( row.eFolderID )

This also works:

import pyodbc
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER=servername;DATABASE=dbname;UID=username;PWD=password')
cursor = cnxn.cursor()
for row in cursor.execute( 'select * from ticket_actions where log_dt > \'2012-09-01\''):
print( row.eFolderID )

Any ideas on how to create a new table with the same structure as the query has?


Answer Source

See Creating and Dropping Database Tables:

Creating … individual tables can be done via the create() … method of Table.

For reading the source structure, see Reflecting Database Objects:

A Table object can be instructed to load information about itself from the corresponding database schema object already existing within the database.
The reflection system can also reflect views.