Add SQL data quality checks

assets/scripts/1_row_count_check.sql

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+/*
+
+# 1. Row count check 
+
+Count the total number of records (or rows) are in the SQL view
+
+*/
+
+SELECT
+    COUNT(*) AS no_of_rows
+FROM
+    view_uk_youtubers_2024;

assets/scripts/2_column_count_check.sql

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+/*
+# 2. Column count check 
+
+Count the total number of columns (or fields) are in the SQL view
+
+*/
+
+
+SELECT
+    COUNT(*) AS column_count
+FROM
+    INFORMATION_SCHEMA.COLUMNS
+WHERE
+    TABLE_NAME = 'view_uk_youtubers_2024'

assets/scripts/3_data_type_check.sql

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+/*
+# 3. Data type check
+
+Check the data types of each column from the view by checking the INFORMATION SCHEMA view
+
+*/
+
+
+SELECT
+    COLUMN_NAME,
+    DATA_TYPE
+FROM
+    INFORMATION_SCHEMA.COLUMNS
+WHERE
+    TABLE_NAME = 'view_uk_youtubers_2024';

assets/scripts/4_duplicate_records_check.sql

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+/*
+
+# 4. Duplicate records check
+
+-- 1. Check for duplicate rows in the view
+-- 2. Group by the channel name
+-- 3. Filter for groups with more than one row
+
+*/
+
+
+-- 1.
+SELECT
+    channel_name,
+    COUNT(*) AS duplicate_count
+FROM
+    view_uk_youtubers_2024
+
+-- 2.
+GROUP BY
+    channel_name
+
+-- 3.
+HAVING
+    COUNT(*) > 1;

assets/scripts/data_quality_tests_full.sql

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+/*
+
+# Data quality tests 
+
+1. The data needs to be 100 records of YouTube channels (row count test)	--- (passed!!!)
+2. The data needs 4 fields (column count test)								--- (passed!!!)
+3. The channel name column must be string format, and the other columns must be numerical data types (data type check)    --- (passed!!!)
+4. Each record must be unique in the dataset (duplicate count check)  --- (passed!!!)
+
+
+Row count - 100 
+Column count - 4
+
+
+Data types
+
+channel_name = VARCHAR
+total_subscribers = INTEGER
+total_views = INTEGER
+total_videos = INTEGER
+
+Duplicate count = 0
+
+
+*/
+
+
+-- 1. Row count check 
+
+SELECT 
+	COUNT(*) as no_of_rows
+FROM 
+	view_uk_youtubers_2024 
+
+
+-- 2. Column count check 
+
+SELECT 
+	COUNT(*) as column_count 
+FROM 
+	INFORMATION_SCHEMA.COLUMNS
+WHERE 
+	TABLE_NAME = 'view_uk_youtubers_2024'
+
+
+
+-- 3. Data type check 
+
+
+SELECT 
+	COLUMN_NAME,
+	DATA_TYPE
+FROM 
+	INFORMATION_SCHEMA.COLUMNS
+WHERE 
+	TABLE_NAME = 'view_uk_youtubers_2024'
+
+
+
+-- 4. Duplicate records check
+
+SELECT 
+	channel_name,
+	COUNT(*) as duplicate_count
+FROM 
+	view_uk_youtubers_2024
+GROUP BY 
+	channel_name 
+HAVING 
+	COUNT(*) > 1