Arithmetic operators ARE: * (multiplication), / (division), DIV (integer division), % (MOD) or remainder, + (addition), - (subtraction). These operators can be used in the SELECT, WHERE, and ORDER BY clauses. Operators are evaluated in the same way as arithmetic in other contexts.
A column alias provides a way to create a clean or more descriptive header for a results set. A column alias cannot be used in a SELECT, WHERE, GROUP BY or HAVING clause due to the order of execution. You must refer to the original column name.
The comparison operators are = (equals), (greater than), =, (not equal), != (not equal). Comparison operators compare two expressions. The result of a comparison results to true or false.
Comparison operators are not case sensitive and are used with text and dates as well as numbers.
The IN operator tests whether an expression is equal to a value or values in a list of expressions. The order of the items in the list does not matter. You can use the NOT operator to test for items not in the list. The IN clause may be used with a subquery.
A SQL index is like the index of a book. It speeds up the retrieval of a record. The relational database management system (RDBMS) can retrieve a record with the index key instead of having to perform a table scan.
The LIKE keyword is used with the WHERE clause. The LIKE keyword and can use two symbols as wildcards. The percent ( % ) symbol matches any number of characters and the underscore ( _ ) matches a single character.
Logical operators are used in the WHERE clause
You may use multiple logical operators in a WHERE clause to create a compound condition. The order of evaluation when multiple operators are used is shown in the table above.
REGEXP operator allows you to do more complex pattern matching than a LIKE keyword/
Some version of REGEXP exists in many computer languages. Refer to the “LIKE and REGEXP” handout for a full list of examples.
Returns a substring starting from the right side of the string.