The CONCAT function is used to concatenate strings.
The || operator can also be used to append one string to another.
The LENGTH function returns the number of
characters (including spaces and hidden characters) in the
string passed to it.
The INSTR function is used to determine if a given string contains
a specified substring. The function returns an integer representing
the position of the substring (if found). If the string is not
found, zero is returned. There are variations of the function that
can be used to
- start the search for the string at a location other than the beginning
- search backwards
- search for a given occurence of the substring
The REPLACE function is used to substitute one substring for another
within a given text string. Oracle also includes a similar function
called TRANSLATE that can be used to perform several single-character,
The UPPER function is used to convert all of the character
in a string to upper case.
The LOWER function is used to convert all of the character
in a string to lower case.
The INITCAP function is used to capitalize the first character
in each substring that appears as an independent word in the string.
It sets all remaining characters to lower case.
LPAD is used to return a given string left-padded to a given length.
The characters used for padding can be specified as well.
RPAD provides the same basic functionality as rpad, but performs right rather than left padding.
The TRIM function is used to remove leading and/or trailing white
space characters from a string.
The TO_CHAR function is used to cast date, numeric or character
data to a character type string. A variety of format models
are available to change the appearance of numeric and date data.
The SOUNDEX function returns a character string containing a
phonetic representation that can be compared with other strings.
Words that are spelled differently but sound alike (in English)
will return the same value. The algorithm for this function
was devised by Donald E. Knuth in his book "The Art of
Computer Programming, Volume 3: Sorting and Searching".