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Asked: 2024-09-27T03:44:34+05:30 In:

how to write not equal to in sql

I’m currently working on a SQL project, and I’m running into some confusion regarding how to properly express “not equal to” in my queries. I know that SQL is a powerful language for interacting with databases, but sometimes the syntax can be a little tricky.

I want to filter results based on certain conditions, specifically to exclude records that match a particular value. However, I’m not sure if there’s a specific operator I should use for this. I’ve come across some references to “<>“, which I believe is meant to indicate not equal to, but I’ve also seen the “!=” operator used in various examples. Are both of these correct, and does it matter which one I use?

Moreover, could you give me an example of how to implement this in a query? For instance, if I have a table of employees and I want to select those who do not work in the “Sales” department, how would I write that query? I want to make sure I’m using the syntax correctly to avoid any errors in my database operations. Any help on this would be greatly appreciated!

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    2 Answers


    1. In SQL, the “not equal to” condition can be expressed primarily in two ways: using the `<>` operator or the `!=` operator. Both of these operators are universally accepted across most relational database management systems like MySQL, PostgreSQL, SQL Server, and others. For instance, if you are querying a database for records where the `status` field is not equal to ‘active’, you could write a SQL statement as follows: `SELECT * FROM users WHERE status <> ‘active’;` or alternatively, `SELECT * FROM users WHERE status != ‘active’;`. Both queries will yield the same results, returning all users whose status does not equal ‘active’.

      It’s important to remember that the choice between `<>` and `!=` might come down to personal or team coding standards, as both are functionally equivalent. However, the `<>` operator is ANSI SQL standard, making it a safer choice for writing portable SQL code that would work across different database systems without compatibility issues. Additionally, when working with NULL values, be aware that comparisons involving NULL will always yield UNKNOWN, rather than TRUE or FALSE. Thus, if your logic requires handling NULLs, consider using `IS NOT NULL` in conjunction with your “not equal” conditions to ensure accurate results.

    2. How to Write Not Equal To in SQL?

      Okay, so you’re trying to figure out how to say “not equal to” in SQL? No worries, it’s pretty simple!

      When you wanna check if something is not equal to something else, you can use this cool symbol: <>. Yeah, that’s it! For example:

      SELECT * FROM my_table WHERE column_name <> 'some_value';

      This means you want to select all the stuff from “my_table” where “column_name” is NOT ‘some_value’. Pretty straightforward, right?

      There’s another way too, but it’s not as common. You can also use !=. So this will do the same thing:

      SELECT * FROM my_table WHERE column_name != 'some_value';

      Just remember, not all SQL databases use !=, so the first one is safer to use. Hope that helps!

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