Where VS Having Clause in SQL: Explore the Difference between Where and Having Clause in SQL
The data found within the SQL series are filtered with the help of two clauses, “Where” and “Having”. Though similar, the differences in these terms arise when it is run and the GROUP BY Clause of the Select command. In this article, we have tried to explain the definition and the difference between where and having clause in SQL.
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Clauses used to filter the records in the SQL series are divided into:
- Where clause
- Having clause
What is the “Where Clause”?
Where Clause is used to fetch/filter the records into rows before they are grouped. These data should specify or meet the mentioned condition. It will select and filter only the required data. Meanwhile, SQL will also implement ‘and’, ‘or’ and ‘not’ in the Where Clause, similar to the boolean condition. Operations such as “select, update and delete” are also carried out by this clause.
Example: Consider a table given below for “BOOKS”
| BOOK_ID | BOOK_NAME | PRICE |
| 89 | A | 230 |
| 90 | B | 430 |
| 91 | C | 324 |
| 92 | D | 730 |
Take the “Query” for example
SELECT BOOK_ID, PRICE FROM BOOKS WHERE PRICE > 350
Output for this query can be given as
| BOOK_ID | PRICE |
| B | 430 |
| D | 730 |
What is the “Having Clause”?
Data from a group is fetched with the help of the “Having” clause. It tries to cater to the condition expected in the final result. The clause is applicable only with Select statements. The clause is used in column functions.
Example: Take the table below for BOOKS
| BOOK_ID | BOOK_NAME | LANGUAGE | PRICE |
| 89 | A | Hindi | 22000 |
| 90 | B | Hindi | 20000 |
| 91 | C | English | 25000 |
Consider, we want the count of books with the count of language > 1. Apply the “Having” clause to the content in the table.
SELECT COUNT(BOOK_ID), LANGUAGE
FROM BOOKS
GROUP BY LANGUAGE
HAVING COUNT(LANGUAGE) > 1;
The output to this is mentioned below:
| COUNT(BOOK_ID) | LANGUAGE |
| 2 | Hindi |
What is the Difference between Where and Having Clause in SQL?
If “Where” clause is used to filter the records from a table that is based on a specified condition, then the “Having” clause is used to filter the record from the groups based on the specified condition. Learn more about what is the difference between Where and Having Clause in SQL from the table below.
Difference between Where and Having Clause in SQL
| Where Clause in SQL | Having Clause in SQL |
| Filter table based data catering to specific condition | Group based data under set condition |
| Applicable without GROUP BY clause | Does not function without GROUP BY clause |
| Row functions | Column functions |
| Select, update and delete statements | Only select statement |
| Applied before GROUP BY clause | Used after GROUP BY clause |
| Used with single row operations such as Upper, Lower and so on | Applicable with multiple row functions such as Sum, count and so on |
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