📍SQL Basics for Everyone : SQL Filtering— Part 3

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📍SQL WHERE

The WHERE clause in SQL is used to filter rows before any grouping or aggregation happens. It specifies which rows should be included in the result set.

The SQL WHERE clause can be combined with the SELECT statement to output only certain rows, based on whether they meet certain conditions:

SELECT column1, column2, ...
FROM table_name
WHERE condition;

🔹SQL WHERE Example

For example, say you’re a data analyst trying to find product reviews with low-star reviews. You could query the reviews table and filter it down to just reviews with less than 4 stars using the SQL clause WHERE stars < 4:

SELECT * 
FROM reviews
WHERE stars < 4;

🔹SQL WHERE with Multiple Conditions

But what if you need to refine your query further by applying multiple conditions?

✅Syntax:

SELECT *
FROM table
WHERE condition1 
  AND/OR condition2
  AND/OR condition3;

Now you’re tasked with finding low-star reviews for a specific user. Let’s say you want to find reviews with less than 4 stars for user ID 362:

SELECT *
FROM reviews
WHERE stars < 4
  AND user_id =…