USAGE.md

Usage

This document covers how to use leopards with different file types

CSV

DictReader from csv module can be used to read csv files as dictionaries as shown below.

import csv
from leopards import Q

data = csv.DictReader(open("data.csv"))
res = Q(data, {"age__gt": 15})

TSV

DictReader from csv module can be used to read tsv files as dictionaries as shown below.

import csv
from leopards import Q

data = csv.DictReader(open("data.csv"), delimiter="\t")
res = Q(data, {"age__gt": 15})

JSON

json.load can be used to read json files as dictionaries as shown below.

import json
from leopards import Q

data = json.load(open("data.json"))
res = Q(data, {"age__gt": 15})

XLS

xlrd library can be used to read xls files as dictionaries as shown below.

import xlrd
from leopards import Q

wb = xlrd.open_workbook("data.xls")
sh = wb.sheets()[0]
keys = sh.row_values(0)
data =[]
for n in range(1, sh.nrows):
    data.append({key: sh.row_values(n)[n2] for n2, key in enumerate(keys)})
res = Q(data, {"age__gt": 15})                

ClickHouse

'clickhouse_driver' library can be used to read data from ClickHouse as dictionaries as shown below.

import clickhouse_connect
client = clickhouse_connect.get_client( host='localhost',  username='default',password='' )
rows = client.execute("SELECT * FROM TABLE")
data = rows.named_results()
res = Q(data, {"age__gt": 15})

MySQL

mysql-client library can be used to read data from MySQL as dictionaries as shown below.

import MySQLdb
from MySQLdb.cursors import DictCursor
from leopards import Q

db=MySQLdb.connect(user='root',password='PASS', database="db", cursorclass=DictCursor)
cursor = db.cursor()
cursor.execute("SELECT * FROM TABLE")
data = cursor.fetchall()
res = Q(data, {"age__gt": 15})