columnTypeDetector 0.1.8

Detect types of columns in delimited files using DuckDB and pandas

Column Type Detector

A simple Python utility to detect the data types of columns in a delimited file using DuckDB and Pandas.

Overview

This tool loads a delimited file into an in-memory DuckDB database treating all columns as VARCHAR.
It analyzes each column to detect data types: int, float, double, str, or null, and outputs a summary table.

Requirements

• Python >=3.12.3+
• duckdb >=1.3.2
• pandas >=2.1.4

Installation

pip install duckdb>=1.3.2 pandas>=2.1.4

Example CLI Wrapper

from columnTypeDetector import load_data_as_varchar, get_column_names, detect_column_types

con = load_data_as_varchar('/content/sample_data/All_Customers.csv',',')

get_column_names(con,"raw_data")

detect_column_types(con,"raw_data")

Sample Output

Here is an example output of the type detection:

col	float	int	null	str	double	total
Address1	0	3	0	2496	0	2499
Address2	0	0	2499	0	0	2499
Address3	0	0	2499	0	0	2499
City	0	0	7	2492	0	2499
City2	0	0	2495	4	0	2499
Company	1	0	0	2498	0	2499
Country	0	0	58	2441	0	2499
CreateDate	0	0	0	2499	0	2499
Currency	0	81	0	2418	0	2499
CustomerID	0	2495	0	4	0	2499
CustomerTier	0	457	171	1871	0	2499
Firstname	0	0	0	2499	0	2499
Lastname	0	0	0	2499	0	2499
MiscDate	0	0	0	2499	0	2499
OrderAmount	0	2498	0	1	0	2499
PrefDelivMethod	0	0	0	2499	0	2499
State	0	107	0	2392	0	2499
Status	0	0	0	2499	0	2499
Zip	0	2410	0	89	0	2499

License

Copyright 2025 Vikas Bhaskar Vooradi

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.