GitLocker: The Coding Marketplace

Description:

tSQLike 1.1.2

tSQLike

SQL-like interface to tabular structured data

Description
tSQLike is a Python3 module that is written with a hope to make tabular data process easier using SQL-like primitives.
Notes
Not that early stage, but still in development: may contain bugs
Usage
from tsqlike import tsqlike

t1 = tsqlike.Table(data=[['h1', 'h2', 'h3', 'h4'],
['a', 'b', 'c', 'd'],
['b', 'c', 'd', 'd'],
['f', 'g', 'h', 'i']],
name='first')
t2 = tsqlike.Table().import_list_dicts(data=[{'h1': 1, 'h2': 2, 'h3': 3},
{'h1': 'd', 'h2': 'e', 'h3': 'f'}],
name='second')
t3 = t1.join(t2, on='first.h4 == second.h1').select('*').order_by('second.h2', direction=tsqlike.ORDER_BY_DEC)
t3.write_csv(dialect='unix')

"first.h1", "first.h2", "first.h3", "first.h4", "second.h1", "second.h2", "second.h3"
"b", "c", "d", "d", "d", "e", "f"
"a", "b", "c", "d", "d", "e", "f"

Installation
pip install tsqlike

Functionality
Table class
The main class of the module
Data processing methods

Name
Status
Description

join
☑
Join two Tables (self and table) on an expression *. Complex, but slow

join_lt
☑
Light, limited, fast and safe Join, that doesn't use eval()

select
☑
Select column(s) from the Table *

select_lt
☑
eval()-free version of select

order_by
☑
ORDER BY primitive of SQL SELECT to sort the Table by a column

group_by
☑
GROUP BY primitive of SQL SELECT to apply aggregate function on a column

Import methods

Name
Status
Description

import_dict_lists
☑
Import a dictionary of lists into Table object

import_list_dicts
☑
Import a list of horizontal arranged dictionaries into the Table

import_list_lists
☑
Import list(list_1(), list_n()) with optional first row as the header

Export methods

Name
Status
Description

export_dict_lists
☑
Export a dictionary of lists

export_list_dicts
☑
Export list of dictionaries

export_list_lists
☑
Export list(list_1(), list_n()) with optional first row as the header

Write methods

Name
Status
Description

write_csv
☑
Make CSV from the Table object and write it to a file or stdout

write_json
☑
Write JSON into file or STDOUT *

write_json_lt
☑
eval()-free version of Table.write_json

write_xml
☐
Write XML. NB: Do we need this?

Private methods

Name
Status
Description

_redimension
☑
Recalculate dimensions of the Table.table

EvalCtrl class
Controls what arguments are available to eval() function

Name
Status
Description

blacklisted
☑
Checks if there is any of the blacklised words in stanza

blacklist_add
☑
Add a new word into the black list

blacklist_remove
☑
Remove the word from the blacklist

Standalone functions

Name
Status
Description

open_file
☑
Open a file

close_file
☑
Close a file

read_json
☑
Read JSON file

read_csv
☑
Read CSV file

read_xml
☐
Read XML. NB: Do we need XML support?

str_to_type
☑
Convert a str to a proper type: int, float or bool

WARNING
Methods Table.join(on=), Table.select(where=) and Table.write_json(export_f=), use eval() function
to run specified expressions within the program. ANY expression, including one that is potentially DANGEROUS
from security point of view, can be passed as the values of the above arguments. It is your duty to ensure correctness
and safety of these arguments and EvalCtrl helps to block potentially dangerous function/method names.
Alternatively you can use Table.join_lt(), Table.select_lt() and Table.write_json(). They are significantly less
powerful, but do not use eval().
Contacts
If you have an idea, a question, or have found a problem, do not hesitate to open an issue or mail me directly:
Mikhail Zakharov zmey20000@yahoo.com