Metadata-Version: 2.1
Name: dbrequests
Version: 1.4.8
Summary: Python package for querying and connecting to databases.
Home-page: https://github.com/INWTlab/dbrequests
Author: Matthaeus Deutsch
Author-email: mdeutsch@outlook.com
License: MIT
Description: # dbrequests
        
        [![Build Status](https://travis-ci.org/INWTlab/dbrequests.svg?branch=master)](https://travis-ci.org/INWTlab/dbrequests)![Publish to PyPi](https://github.com/INWTlab/dbrequests/workflows/Publish%20to%20PyPi/badge.svg?branch=master)
        
        **dbrequests is a python package built for easy use of raw SQL within python and pandas projects.**
        
        It uses ideas from [records](https://github.com/kennethreitz/records/) and is built using [sqlalchemy-engines](https://www.sqlalchemy.org/), but is more heavily integrated with pandas. It aims to reproduce the pilosophy behind the R-package [dbtools](https://github.com/INWT/dbtools/).
        
        
        _Database support includes RedShift, Postgres, MySQL, SQLite, Oracle, and MS-SQL (drivers not included)._
        
        ## Usage
        
        ### Send queries and bulk queries
        
        Easy sending of raw sql and output as pandas DataFrames, with credentials given as dictionary (for an example see creds_example.json) or the url of the database:
        
        ```python
        from dbrequests import Database
        
        db = Database(creds=creds)
        df = db.send_query("""
            SELECT * FROM test;
            """)
        df # table test as pandas DataFrame
        ```
        
        You can put the sql query in a file and direct `send_query` to the file. The sql-file may be parametrized:
        
        ```sql
        SELECT {col1}, {col2} FROM test;
        
        ```
        
        ```python
        from dbrequests import Database
        
        db = Database(creds=creds, sql_dir = '/path/to/dir/')
        db.send_query('select', col1='id', col2='name')
        df # table test, including columns 'id', 'name' as pandas DataFrame
        ```
        
        You can also pass arguments to pandas `read_sql`-Function:
        
        ```python
        from dbrequests import Database
        
        db = Database(creds=creds, sql_dir = '/path/to/dir/')
        db.send_query('select', col1='id', col2='name', index_col='id')
        df # table test, including column 'name' as pandas DataFrame with index 'id'
        ```
        
        You may also send queries with no table as output to the database via `send_bulk_query`, which exhibits the same behavior as `send_query`:
        
        ```python
        db.send_bulk_query('drop test from test;')
        ```
        
        ### Send data
        
        Easy sending of pandas Dataframes in multiple modes:
        
        ```python
        db.send_data(df, 'table', mode='insert')
        ```
        
        Supported modes are:
          - 'insert': Appending new records. Duplicate primary keys will result in errors (sql insert into).
          - 'truncate': Delete the table and completely rewrite it (sql truncate and insert into).
          - 'replace': Replace records with duplicate primary keys (sql replace into).
          - 'update': Update records with duplicate primary keys (sql insert into duplicate key update).
        
        ### Utilities
        
        - Comments can be automatically removed from SQL code by adding `remove_comments=True` either to the Database defintion or send_query. This is especially useful if outcommenting code blocks including parametized variables and thus `{}`. The default of this behavior is `False`.
        - Percentage signs can be transfered to a Python readable way by adding `escape_percentage=True` either to the Database definition or send_query. This means percentage signs dont have to be escaped manually when sending them via Python. The default is `False`.
        - Database.get_table_names will give existing tables in the database
        - Parameters such es `chunksize` for `pandas.to_sql` may be given to the wrapper function `send_data` and are handed over to pandas. The same is true for `send_query`.
        - For transactions the context manager `transaction` may be of use.
        
        ## Installation
        
        The package can be installed via pip:
        
        ```
        pip install dbrequests
        ```
        
        ## Extensibility
        dbrequests is designed to easily accommodate different needs in the form of drivers / dialects. For examples of how to extend the capabilities of the Connection class, see connection_subclass.py under examples.
        
        ### Existing extensions
        - MySQL / MariaDB: use
        ```
        from dbrequests.mysql import Database
        ```
        for using the MySQL specific extension as Database connector. The extension provides MySQL specific functionalities, like using `load data infile` for writing data to tables.
        
        
        ## Version 1.0
          - implemented send_data and send_query wrappers for pandas sql-functionality
        
        ## Version 1.0.8
          - renamed to dbrequests
        
        ## Version 1.1
          - added handling of percentage signs
          - added possibility of automated comment removal
          - ensured the compatibility of raw SQL code with code sent via dbrequests
        
        ## Version 1.2
          -  changed static loading of the connection class to a flexible model, allowing to override connections for different SQL drivers
        
        ## Version 1.3
          - added mysql backend for specific mysql and mariadb support
          - added possibility for send_data to use infile for mysql databases
        
        ## Version 1.3.8
          - dbrequests.mysql module:
            - see #11 for motivation on moving dialect specific implementation into extras
            - see #15 for mysql specific send_data via load data local infile
        
        ## Version 1.3.9
          - dbrequests.mysql:
            - see #20 for memory efficient send_data using datatable
        
        ## Version 1.3.10
          - dbrequests.mysql:
            - see #24 for bugfix while writing to csv
        
        ## Version 1.3.11
          - dbrequests.mysql:
            - see #28 for bugfix when sending escape sequences
        
        ## Version 1.3.12
          - dbrequests.mysql:
            - see #22 for performance improvements for send_query when reading large datasets
            - support for pymysql and mysqldb
        
        ## Version 1.3.13
          - dbrequests.mysql
            - see #30: fixes handling of None/NULL values in columns
        
        ## Version 1.3.14
          - dbrequests.mysql:
            - see #32 for bugfix in send_query for empty result sets
        
        ## Version 1.3.15
          - dbrequests:
            - see #27 for bugfix in Database class when specifiying a port in a
              credentials object.
            - the argument 'creds' in the init method of a database class is now
              deprecated
            - the argument 'db_url' can now handle str and dict type; str is a
              sqlalchemy url; a dict a credentials object
            - credential objects can now have additional fields which will be used as
              elements in connect_args for sqlalchemies create_engine: see #12
          - dbrequests.mysql
            - see #36 for bugfix while sending an empty frame
        
        ## Version 1.3.16
          - dbrequests.mysql
            - see #35: New send_data modes: update_diffs, insert_diffs, replace_diffs
        
        ## Version 1.3.17
          - dbrequests.mysql
            - new function in database: send_delete for deleting rows in a database.
            - send_data in mode 'update' now allows to send only partial subset of
              columns.
        
        ## Version 1.4.0
          - dbrequests.mysql
            - bugfix in send_data with mode [update|insert|replace]_diffs: same as #36
        
        ## Version 1.4.1
          - dbrequests.mysql
            - bugfix for upstream bug in mariadb: sending diffs needs persisten tables
              instead of temporary.
        
        ## Version 1.4.2
          - dbrequests.mysql
            - creating temorary removing partitions and system versioned from temporary
              tables.
            - new mode for send data: sync_diffs: update differences and delete
              deprecated rows.
            - new mode for delete data: in_delete_col: mark rows to delete, then delete.
            - bugfix for temporary tables: now properly removes tables.
        
        ## Version 1.4.3-5
          - dbrequests.mysql
            - More stable and reliable Version of sync_diffs mode for sending data.
              Respects scarce resources on the mysql server.
        
        ## Version 1.4.6
          - dbrequests.mysql
            - HOTFIX #51: Bug with latest datatable version
        
        ## Version 1.4.7
          - dbrequests.mysql
            - bugfix of #52
        
        ## Version 1.4.8
          - dbrequests.mysql
            - fix for creating temporary files on Windows.
        
        
Platform: UNKNOWN
Classifier: Development Status :: 4 - Beta
Classifier: Intended Audience :: Developers
Classifier: Natural Language :: English
Classifier: License :: OSI Approved :: MIT License
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Programming Language :: Python :: 3.8
Description-Content-Type: text/markdown
Provides-Extra: pg
Provides-Extra: redshift
Provides-Extra: mysql
