TO_CHAR(d[, format])
The TO_CHAR function transforms a date or a "d" number into a string of symbols. If the "format" parameter is specified it is used to control the result structure. Format string consists of format elements. Each element returns some part of a value, for example, it can be the month. Basic format elements used in the TO_CHAR function are described in the table:
| Element of the date format | Description |
| "text" | A text enclosed in double quotes is reproduced unchanged. |
| D | Day of the week (1 - 7). |
| DAY | Name of the day padded with spaces to the length of nine symbols. |
| DD | Day of the month (1 - 31). |
| DDD | Day of the year (1 - 366). |
| DY | Abbreviated weekday name. |
| HH12 | Hour (1 - 12). |
| HH24 | Hour (1 - 24). |
| IW | Week of the year (1 - 52, 1 - 53) based on the ISO standard. |
| IYY, IY, I | Last three, two or one digit of the year. |
| YYYY | Four-digit indication of the year. |
| Ml | Minutes (0 - 59). |
| MM | Month (1 - 12). |
| MON | Abbreviated name of the month. |
| MONTH | Name of the month padded with spaces to the length of nine symbols. |
| Q | Quarter (1 - 4). |
| RM | Month in Roman numerals (I - XII). |
| SS | Seconds (0 - 59). |
| SSSSS | Seconds starting from midnight (0 - 86399). |
| Element of numeric format | |
| 9 | A digit is displayed. The leading zero is replaced with a space. |
| 0 | A digit is displayed. The leading zero is displayed. |
| EEEE | The result is displayed in the exponential notation. |
| G | A group separation symbol is displayed in the specified position. |
TO_CHAR(SYSDATE,'IYYY') = VAL
Value of the VAL field (Date type) should match the current year.
TO_LONGCHAR(d)
The TO_LONGCHAR functions transforms the input value "d" into a long string (LONGCHAR).
TO_LONGCHAR(VAL) IS NOT NULL
The VAL field should not contain the NULL value after it has been transformed into a long string.
TO_DATE(string[, format])
The TO_DATE functions transforms a string into the Date type. The "format" argument is a string of the date format. Format elements are the same as the date format elements for the TO_CHAR function.
SYSDATE > TO_DATE(VAL,'DD.MM.YYYY')
The VAL field of the string type is to contain a value corresponding to the date, but less than the current date.
TO_NUMBER(string[, format])
The TO_NUMBER function transforms the "string" string into a numerical value. The "format" argument is a string of the number format. Format elements are the same as the number format elements for the TO_CHAR function.
100.00 > TO_NUMBER(VAL,'999.99')
The VAL field of the string type is to contain a value corresponding to the number, but less than 100.00.
See also: