Note: Translate and replace are
very similar in their appearance but can produce very different results. Translate replaces by position, the first character
of the list to match is replaced by the first character of the replacement list. The second character with the second, and
if there are characters in the list to match that do not have positional equivalents in the replacements list they are dropped.
Replace replaces the string to match with the replacement string. The replacement of a single character is the same as that of
TRANSLATE. |
| Syntax |
TRANSLATE(
str1 VARCHAR2 CHARACTER SET ANY_CS,
src VARCHAR2 CHARACTER SET STR1%CHARSET,
dest VARCHAR2 CHARACTER SET STR1%CHARSET)
RETURN VARCHAR2 CHARACTER SET STR1%CHARSET; |
| |
| Translate Built-in String Function |
Single Character
Replacement |
TRANSLATE(<string>, <'list_to_match'>,<'replacements_list'>)
This demo replaces all commas with vertical bars. |
SELECT TRANSLATE('comma,delimited,list', ',', '|')
FROM DUAL; |
Multiple Character
Replacement |
The following takes a DNA sequence and returns its complement |
SELECT TRANSLATE('CAG-TTT-GAC-ACA-TGG-ATC', 'ACGT', 'GATC') DNA
FROM DUAL; |
Character Replacement
And Elimination |
The a is replaced with an e, the h has no complement and is dropped. |
SELECT TRANSLATE('So What', 'ah', 'e')
FROM DUAL; |
Eliminating Double
Quotes |
Capital A is replaced with capital A. The double quote is eliminated because there is no match. |
SELECT TRANSLATE('"Darn double quotes
"', 'A"', 'A')
FROM DUAL; |
| Encryption / Decryption |
In this demo a string is first encrypted then decrypted |
SELECT TRANSLATE('this is a secret',
'abcdefghijklmnopqrstuvxyz', '0123456789qwertyuiop[kjhbv')
FROM DUAL;
SELECT TRANSLATE('p78o 8o 0 o42i4p',
'0123456789qwertyuiop[kjhbv', 'abcdefghijklmnopqrstuvxyz')
FROM DUAL; |
| Counting Vowels |
In this demo the number of vowels in
the string is counted |
WITH data AS (SELECT 'Whose line is it anyway' line
FROM DUAL)
SELECT LENGTH(line)-LENGTH(TRANSLATE(line,'xaeiou','x')) nbVowels
FROM data; |
|
|
| Replace Built-in String Function |
| REPLACE (overload 1) |
REPLACE(
srcstr VARCHAR2 CHARACTER SET ANY_CS,
oldsub VARCHAR2 CHARACTER SET SRCSTR%CHARSET,
newsub VARCHAR2 CHARACTER SET SRCSTR%CHARSET := NULL)
RETURN VARCHAR2 CHARACTER SET SRCSTR%CHARSET; |
| REPLACE (overload 2) |
REPLACE(
srcstr CLOB CHARACTER SET ANY_CS,
oldsub CLOB CHARACTER SET SRCSTR%CHARSET,
newsub CLOB CHARACTER SET SRCSTR%CHARSET := NULL)
RETURN CLOB CHARACTER SET SRCSTR%CHARSET; |
Single Character
Replacement |
REPLACE(<string>, <'string_to_match'>,<'replacements_string'>) |
SELECT REPLACE('So
What', 'o', 'ay')
FROM DUAL; |
Multiple Character
Replacement |
Replacement of a single character with a phrase |
SELECT REPLACE('An idea that is not
dangerous is unworthy of being called an idea at all.',
'n idea', ' software
program') TRUTH
FROM DUAL;
|