What is SQL AND?

SQL AND is an operator that is used to create a query with different parameters. An entry will only be considered if all the conditions in the query are met.

What is SQL AND and what is it used for?

The operator SQL AND is used in the Structured Query Language to include or exclude certain results when querying information. It’s an important tool for performing searches based on specific criteria. It can be combined with SQL OR when conducting an SQL WHERE query. Both operators function according to Boolean algebra, where a response can only contain two logical values: true or false. Within this framework, OR allows for more results to be included. SQL AND, on the other hand, is more restrictive.

What is the syntax for SQL AND?

SQL AND is used together with WHERE in a SELECT query. The syntax looks like this:

SELECT column1, column2, …
FROM name_of_table
WHERE condition1 AND condition2 AND condition3 AND …;

Using the SQL command SELECT, choose the columns that should be considered in your query. You can specify a single column or multiple columns. The FROM clause specifies the table where data should be retrieved. After WHERE, you can list all the conditions that an entry must meet in order to be included in the results. The SQL operator AND only outputs entries in the results if they meet all the conditions. OR , on the other hand, outputs entries if they fulfill at least one of the conditions.

SQL AND examples

It’s easier to understand how SQL AND works with an example. Let’s imagine a company that has branches in different countries. We’re going to create a table that contains an ID number for each branch, the city and the country where each branch is located, and the number of employees at each branch. We’re going to name the table ‘Branches’.

Now, we’re going to initiate a query using the AND operator. This will allow us to exclude certain entries from our search results. In the example below, we want to find branches located in England with more than 20 employees. Here’s what the SQL query looks like:

SELECT ID, City, Country, Staff
FROM Branches
WHERE Country = 'England' AND Staff > 20;

The result looks like this:

The Manchester branch was excluded from our results, because despite being located in England, it has fewer than 20 people on its staff. The branches in Frankfurt and Buenos Aires weren’t included in the list because they are not located in England. Since the branch in Tokyo didn’t match either of the criteria, it was excluded as well.

How to combine AND and OR operators in SQL

It’s also possible to combine the AND operator in SQL with OR. To show you how this works, we’ll use the table from the example above. Now we are going to search the entries in the Branches table to look for branch locations that have more than 20 employees and are located either in England or Argentina. In order to do this, we need to use brackets. Here’s how to write the code for this query:

SELECT ID, City, Country, Staff
FROM Branches
WHERE (Country = 'Germany' OR Country = 'Argentina') AND Staff > 20;

And here’s the result:

Which operators are similar to SQL AND?

The SQL AND operator isn’t the only operator that can be used to filter data. In addition to the OR operator, there’s another operator you can use to search a dataset according to specific criteria. With the NOT operator, you can create conditions to filter entries based on criteria that they do not meet. For instance, you could use this operator to show all branches that aren’t located in England.