Character Functions : Introduction « Character String Functions « Oracle PL/SQL Tutorial

1. Oracle PL/SQL Tutorial
2. Character String Functions
3. Introduction

Character Functions accept character input.

The input may come from a column in a table or from any expression.

Character Functions List

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 y to x 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 find_string occurs.
6. INSTRB(x) returns the location of a string within another string, but returns the value in bytes for a single-byte character system.
7. LENGTH(x) returns the number of characters in x.
8. LENGTHB(x) returns the length of a character string in bytes, except that the return value is in bytes for single-byte character sets.
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 to handle 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.