How to write not equal in Oracle
The operator used to express inequality in Oracle is "!==", which is used to compare two values and return a Boolean value whether they are equal. The syntax is: expression1 != expression2. This operator can also be expressed as "<>" and is used to filter for unequal values.
Inequality operator in Oracle
In Oracle, the operator used to express inequality is "!==".
Usage
The "!==" operator compares two values and returns a Boolean value indicating whether they are not equal. The syntax is:
<code>表达式1 != 表达式2</code>
where "expression 1" and "expression 2" can be constants, variables, columns or expressions.
Examples
The following are some examples showing the use of the "!==" operator:
SELECT * FROM employees WHERE salary != 10000; SELECT product_name FROM products WHERE price != 15.99;
These queries will return items that satisfy the given All rows of the condition, that is, the employee's salary is not equal to 10,000, or the price of the product is not equal to 15.99.
Note
The "!==" operator is equivalent to the "<>" operator and can also be used to express inequality.
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