There is a problem with information submitted for this request. Review/update the information highlighted below and resubmit the form. From Mayo Clinic to your inboxSign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. ErrorEmail field is required ErrorInclude a valid email address Learn more about Mayo Clinic’s use of data.To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail. What is the difference between HAVING and WHERE clause? What is the difference between HAVING and WHERE clause is one the most popular question asked in interviews especially to the freshers? Though these two clauses are very similar and they primarily restrict the tuples returned by the SELECT statement, the main difference arises when used with the GROUP BY clause. So, lets first learn about these two clauses and then their differences. WHERE ClauseThe WHERE clause is used to fetch the data which specify the given condition. It is used to filter records and select only necessary records. It is used with SELECT, UPDATE, DELETE, etc. query. The SQL also implements and, or, and not in the WHERE clause which is known as the boolean condition. Example: Take an example of a table Transaction that has ‘Item’, ' Month' and ‘Amount ’ as attributes. If we want to calculate the total sale by two products TV and Fridge then our Query statement would be:
The output of the above query will be: HAVING ClauseThe HAVING clause is generally used along with the GROUP BY clause. This clause is used in the column operation and is applied to aggregate rows or groups according to given conditions. Example: Consider the above example. Now, if we want to calculate the Net_amount of the total sale by two products TV and Fridge then our query statement would be:
The output of the above query will be: Now, if we want only those items which have the net_amount greater than 1200. The query can be written as:
1The output of the above query will be: This cannot be done in the WHERE clause. It generates an error message when we use the WHERE clause with the aggregate functions. Difference between WHERE and HAVING clause
Example: The following query has the same results. The WHERE clause uses the “age” index but the having clause will scan the full table instead of directly looking at the "age" column.
22. HAVING clause 3This was a discussion on the differences between WHERE and HAVING clause. Hope you learned something new today. Do share this blog with your friends to spread the knowledge. Visit our YouTube channel for more content. You can read more blogs from here . Wann wird having verwendet?HAVING ist eine Bedingung, die auf aggregierte Werte angewendet werden kann. Die WHERE Bedingung kann zum Beispiel auf gruppierte Werte (GROUP BY) nicht angewendet werden, dafür muss man HAVING verwenden.
Wann benutzt man having SQL?Das SQL HAVING–Statement ist das SQL WHERE in einem SQL GROUP BY-Statement. Es ermöglicht eine gruppierte Ergebnismenge einzuschränken. Mit SQL HAVING kann die Ergebnismenge auf Basis der Aggregatfunktionen (AVG, COUNT, MAX, MIN, SUM) eingeschränkt und ausgegeben werden.
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