For example, if we wanted to get information about all owners whose first name is not Homer, we could do the following:. If you have multiple conditions, you can use multiple operators whether both the same operators or different. Once you start using more conditions, you should use parentheses to surround the conditions that you want to be evaluated first. Of course, this itself could be negated with the NOT operator, which would then give us the same result that the equal to! The SQL Server not equal operators are used to test that one value, often a column, does not match the value of another.
This SQL query will return every row from the Sales. The query shown above would work exactly the same if the WHERE clause used one of the alternative operators as shown below. In fact, this is true in any situation. These operators can be used interchangeably in SQL Server. Working with NULL values can yield unexpected results. Consider, again, the query above. Note that in the output the first row is order number 2.
That is because order number 1 was associated to Salesperson number 2 and was excluded. There are several rows that were packed by person number 3 along with a series of NULL values for the column.
The result set, however, is highly unexpected. The issue here is that the not equal operators cannot be used to compare to NULL values and will always evaluate as false when a NULL value is involved. To avoid confusion when writing SQL code, this author likes to logically think of the operator this way.
If left-hand operator not lower than right-hand operator then condition will be true and it will return matched records. If we run following SQL statement for not less than operator it will return records where empid not lower than 2. When we execute the above SQL not less than operator query, we will get the result like as shown below. In sql, not greater than operator is used to check whether the left-hand operator is not higher than the right-hand operator or not.
If left-hand operator not higher than right-hand operator then condition will be true and it will return matched records. If we run following SQL statement for not greater than operator it will return records where empid not higher than 2. When we execute the above SQL not greater than operator query, we will get the result like as shown below. For more information related to comparison operators in sql server check the following information.
The sql equal operator is used to check whether two expressions equal or not. The sql not equal operator is used to check whether two expressions equal or not. Does ES6 make JavaScript frameworks obsolete? Podcast Do polyglots have an edge when it comes to mastering programming Featured on Meta. Now live: A fully responsive profile.
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