University:
American Baptist College
Course:
CSCI 1534 | Data Analysis and Visualization
Academic year:

2023
Views:

437

Pages:

2
Author:

Muthia M.

Cleaning Data There’s several way to clean data two of them are 1. Trimming data, to clean unused spaces on the data 2. Format date/ date time into readable date format such as Day, Month, Year Trim () With trim () we can remove all spaces from text except for single spaces between words. For example: Query results : Change Data Type In some case manipulate date type column to enlarge our analysis, one of that is change date type to string type as name of the day. In BigQuery: SELECT CURRENT_DATE () AS date, FORMAT_DATE ('%A', CURRENT_DATE()) AS dow In Python: df['date']. dt.day_name() In Excel Format ([coloumn date], ‘dddd’) For Duplicate Data Load is copying data from one electronic file or database into another. We move transformed data to a data repository. This statement is used to select no duplicate data. The DISTINCT keyword operates on a column. The syntax looks like this For example: SELECT DISTINCT city FROM customer SELECT DISTINCT * FROM customer