| A | B |
|---|
| CASE | Implements conditional processing (IF-THEN-ELSE logic) within a SQL statement; it meets the ANSI standard. |
| CHAR(size) | The CHAR data type stores fixed-length character strings. (Size) refers to the maximum number of characters. The database allocates a fixed space designated by (size), regardless of how many characters the actual data takes up. The default size is 1, the max size is 2000. |
| COALESCE | Returns the first non-null expression in the list. |
| Conditional Expressions | Implement IF-THEN-ELSE logic. |
| Conversion Functions | Functions that convert a value from one data type to another. |
| Data Type Conversion | To convert data of one data type to a different data type. |
| DATE data type | Date and time value between January 1, 4712 B.C. and A.D. December 31, 9999. |
| DD Date Format | Numeric day of the month. |
| DECODE | Implements conditional processing (IF-THEN-ELSE logic) within a SQL statement; it is specific to the Oracle syntax. |
| Domain | Set of all possible values of an independent variable of a function. |
| DY Date Format | Name of the day; three-letter abbreviation |
| Explicit Data Type Conversion Functions | Fully and clearly expressed; leaving nothing implied |
| Expression | A symbol or combination of symbols that represents a quantity or a relationship between quantities. |
| fm | format-model’; used to remove padded blanks or to suppress leading zeros. |
| IF-THEN-ELSE | A programming IF statement that checks condition(s), if the condition(s) is true the THEN statement(s) get accomplished; if the condition is false the ELSE statement(s) gets accomplished. |
| Implicit Data Type Coversion Functions | Implied or understood though not directly expressed. |
| Nesting Functions | Is using a function call as an argument to another function. |
| NULLIF | NULLIF compares two expressions; if they are equal, the function returns null; if they are not equal, the function returns the first expression. |
| NUMBER(size) | A data type that is commonly used for numbers. (Size) refers to the maximum number of digits. |
| NVL | Converts nulls to an actual value, or to force group functions to include null values. |
| NVL2 | Examines the first expression; if the first expression is not null, it returns the second expression; if the first expression is null, it returns the third expression. |
| RR Date Format | Century value depends on the specified year and the last two digits of the current year. |
| TO_CHAR Function | Converts dates or numbers to character strings with optional formatting. |
| TO_DATE Function | Converts a character string representing a date to a date value with optional formatting. |
| TO_NUMBER | Converts a character string containing digits to a number with optional formatting. |
| WW Format | Numeric week of the year. |
| YYYY Format | Full year in numbers. |
| VARCHAR2 | Stores variable-length strings. |
