Character Functions
| Function | Syntax | Description |
| CONCAT | CONCAT(char1, char2) | returns char1 concatenated with char2 |
| LOWER | LOWER(char) | returns char, with all letters lowercase |
| UPPER | UPPER | returns char, with all letters uppercase |
| LTRIM | LTRIM(char [, set ]) | removes from the left end of char all of the characters contained inset |
| RTRIM | RTRIM(char [, set ]) | removes from the right end of char |
| SUBSTR | { SUBSTR| SUBSTRB| SUBSTRC}(char, position [, substring_length ]) | return a portion of char, beginning at character position, substring_length characters long |
| REPLACE | REPLACE(char, search_string[,replacement_string ]) | Replace the character. |
Numeric Functions
| Function | Syntax | Description |
| ABS | ABS(n) | returns the absolute value of n |
| CEIL | CEIL(n) | returns smallest integer greater than or equal to n |
| FLOOR | FLOOR(n) | returns largest integer equal to or less than n. |
| ROUND | ROUND(n [, integer ]) | returns n rounded to integer places to the right of the decimal point |
| TRUNC | TRUNC(n1 [, n2 ]) | returns n1 truncated to n2 decimal places |
| Function | Syntax | Description |
| NULLIF | NULLIF(expr1, expr2) | compares expr1 and expr2. If they are equal, then the function returns null. If they are not equal, then the function returns expr1. |
| NVL | NVL(expr1, expr2) | allows you to replace null with the second parameter |
| NVL2 | NVL2(expr1, expr2, expr3) | If expr1 is not null, then NVL2 returns expr2. If expr1 is null, then NVL2 returns expr3. |
| DECODE | DECODE(expr,search,result [, search, result ]… [, default ]) | Compares expr to each search value one by one. If expr is equal to a search, the corresponding result is returned. If no match is found, default is returned. |
| CASE | CASE { expr WHEN comparison_expr THEN return_expr [ WHEN comparison_expr THEN return_expr ]… | WHEN condition THEN return_expr [ WHEN condition THEN return_expr ]… } [ ELSE else_expr ] END | returns value based on different conditions |