如何使用python将.csv文件转换为.db文件？

Question

I want to convert a csv file to a db (database) file using python. How should I do it ?

Answer 1

1. You need to find a library that helps you to parse the csv file, or read the file line by line and parse it with standard python, it could be as simple as split the line on commas.

2. Insert in the Sqlite database. Here you have the python documentation on SQLite . You could also use sqlalchemy or other ORM .

Another way, could be using the sqlite shell itself.

Answer 2

I don't think this can be done in full generality without out-of-band information or just treating everything as strings/text. That is, the information contained in the CSV file won't, in general, be sufficient to create a semantically “satisfying” solution. It might be good enough to infer what the types probably are for some cases, but it'll be far from bulletproof.

I would use Python's csv and sqlite3 modules, and try to:

• convert the cells in the first CSV line into names for the SQL columns (strip “oddball” characters)
• infer the types of the columns by going through the cells in the second CSV file line (first line of data), attempting to convert each one first to an int , if that fails, try a float , and if that fails too, fall back to strings
• this would give you a list of names and a list of corresponding probably types from which you can roll a CREATE TABLE statement and execute it
• try to INSERT the first and subsequent data lines from the CSV file

There are many things to criticize in such an approach (eg no keys or indexes, fails if first line contains a field that is a string in general but just so happens to contain a value that's Python-convertible to an int or float in the first data line), but it'll probably work passably for the majority of CSV files.