Pl/Sql - String Function

1 ASCII(x);
Returns the ASCII value of the character x.
2 CHR(x);
Returns the character with the ASCII value of x.
3 CONCAT(x, y);
Concatenates the strings x and y and return the appended string.
4 INITCAP(x);
Converts the initial letter of each word in x to uppercase and returns that string.
5 INSTR(x, find_string [, start] [, occurrence]);
Searches for find_string in x and returns the position at which it occurs.
6 INSTRB(x); 
Returns the location of a string within another string, but returns the value in bytes.
7 LENGTH(x); 
Returns the number of characters in x.
8 LENGTHB(x); 
Returns the length of a character string in bytes for single byte character set.
9 LOWER(x); 
Converts the letters in x to lowercase and returns that string.
10 LPAD(x, width [, pad_string]) ; 
Pads x with spaces to left, to bring the total length of the string up to width characters.
11 LTRIM(x [, trim_string]); 
Trims characters from the left of x.
12 NANVL(x, value); 
Returns value if x matches the NaN special value (not a number), otherwise x is returned.
13 NLS_INITCAP(x); 
Same as the INITCAP function except that it can use a different sort method as specified by NLSSORT.
14 NLS_LOWER(x) ; 
Same as the LOWER function except that it can use a different sort method as specified by NLSSORT.
15 NLS_UPPER(x); 
Same as the UPPER function except that it can use a different sort method as specified by NLSSORT.
16 NLSSORT(x); 
Changes the method of sorting the characters. Must be specified before any NLS function; otherwise, the default sort will be used.
17 NVL(x, value); 
Returns value if x is null; otherwise, x is returned.
18 NVL2(x, value1, value2); 
Returns value1 if x is not null; if x is null, value2 is returned.
19 REPLACE(x, search_string, replace_string); 
Searches x for search_string and replaces it with replace_string.
20 RPAD(x, width [, pad_string]); 
Pads x to the right.
21 RTRIM(x [, trim_string]); 
Trims x from the right.
22 SOUNDEX(x) ; 
Returns a string containing the phonetic representation of x.
23 SUBSTR(x, start [, length]); 
Returns a substring of x that begins at the position specified by start. An optional length for the substring may be supplied.
24 SUBSTRB(x); 
Same as SUBSTR except the parameters are expressed in bytes instead of characters for the single-byte character systems.
25 TRIM([trim_char FROM) x); 
Trims characters from the left and right of x.
26 UPPER(x); 
Converts the letters in x to uppercase and returns that string.