Oracle and SQL Server comparison operators are nearly identical.
| Operator | Oracle | SQL Server |
| Equal to | = | = |
| Greater than | > | > |
| Less than | < | < |
| Greater than or equal to | >= | >= |
| Less than or equal to | <= | <= |
| Not equal to | !=, ^=, < > | !=, <> |
| Not greater than | N/A | !> |
| Not less than | N/A | !< |
| In any member in set | IN | IN |
| Not in any member in set | NOT IN | NOT IN |
| Any value in set | ANY, SOME | ANY, SOME |
| All values in set | ALL | ALL |
| Like pattern | LIKE | LIKE |
| Not like pattern | NOT LIKE | NOT LIKE |
| Value between | BETWEEN | BETWEEN |
| Value not between | NOT BETWEEN | NOT BETWEEN |
| Value exists | EXISTS | EXISTS |
| Value does not exist | NOT EXISTS | NOT EXISTS |
| Value {is | is not} NULL | IS NULL, IS NOT NULL | IS NULL, IS NOT NULL |
The SQL Server LIKE keyword offers some useful wildcard search options that are not supported by Oracle. In addition to supporting the % and _ wildcard characters, the [ ] and [^] characters are also supported.
If you are familiar with the UNIX operating system, you recognize these characters and their capability. The [ ] character set is used to search for any single character within a specified range. For example, if you are searching for the characters a through f in a single character position, you can specify this with '[a-f]' or '[abcdef]'.
The [^] wildcard character is used to specify those characters NOT in the specified range. For example, if any character except for a through f is acceptable, you use '[^a - f]' or '[^abcdef]'. The usefulness of these additional wildcard characters is shown in the table.
| Oracle | SQL Server |
| SELECT * FROM STUDENT_ADMIN.STUDENT WHERE LNAME LIKE 'A%' OR LNAME LIKE 'B%' OR LNAME LIKE 'C%' |
SELECT * FROM STUDENT_ADMIN.STUDENT WHERE LNAME LIKE '[ABC]%' |
For more information about the LIKE keyword, see the Microsoft SQL Server Database Developer's Companion.
Oracle uses two pipe symbols (||) as the string concatenation operator, while SQL Server uses the plus sign (+). This difference requires minor revision in your application program code.
| Oracle | SQL Server |
| SELECT FNAME||' '||LNAME AS NAME FROM STUDENT_ADMIN.STUDENT |
SELECT FNAME +' '+ LNAME AS NAME FROM STUDENT_ADMIN.STUDENT |