SQL String Functions

Introduction

SQL Server String functions are scalar functions that perform an operation on a string input values and return a string or numeric value. SQL Server String built-in function. In this section, we cover string function seen in SQL. Different RDBMS may employ different string functions.

List Of String Function

1. ASCII
2. CHAR
3. REVERSE
4. UPPER
5. LEFT
6. LEN
7. LOWER
8. LTRIM
9. NCHAR
10. REPLACE

Explanation Of All Above Functions

1. ASCII
   
   Return the ASCII code value of the left most character of the current string. ASCII() works for characters with numeric values from 0 to 255. Here’s Figure 1.1.
   
   
   
   
2. CHAR
   
   Convert an int ASCII code to character. Null Values are skipped. It is opposite to ASCII() function. Here’s Figure 1.2.
   
   
   
   
3. REVERSE
   
   Return the string with the order the characters reversed. See reverse string in Figure 1.3.
   
   
   
   
4. UPPER
   
   Returns a UPPER case string. Here’s Figure 1.4 and you can see lower string value converted to upper case string.
   
   
   
   
5. LEFT
   
   Returns the left part of a character string with the specified number of characters. Here’s Figure 1.5 Left() function two arguments:
   1. String
   2. Length of string
   
   
   
   
6. LEN
   
   Returns the number of characters, instead of the number of bytes of the specified string. Length of string in Figure 1.6.
   
   
   
   
7. LOWER
   
   Returns a character string after converting uppercase string to lower strings. Here’s string is UPPER case string To lower case string.
   
   
   
   
8. LTRIM
   
   Remove leading blanks spaces in string.
   
   
   
   
9. NCHAR
   
   Return specified integer code defined by Unicode standard. Same as Char() function. (Figure 1.9).
   
   
   
   
10. REPLACE
    
    Replace one string to second string. Replace() performs a case-sensitive match when searching for form_str.