SQL Server provides a variety of string functions that allow you to manipulate and work with character or text data. Here are some commonly used SQL Server string functions:
| Function | Description |
| ASCII | Return the ASCII code value of a character |
| CHAR | Convert an ASCII value to a character |
| CHARINDEX | Search for a substring inside a string starting from a specified location and return the position of the substring. |
| CONCAT | Join two or more strings into one string |
| CONCAT_WS | Concatenate multiple strings with a separator into a single string |
| DIFFERENCE | Compare the SOUNDEX() values of two strings |
| FORMAT | Return a value formatted with the specified format and optional culture |
| LEFT | Extract a given a number of characters from a character string starting from the left |
| LEN | Return a number of characters of a character string |
| LOWER | Convert a string to lowercase |
| LTRIM | Return a new string from a specified string after removing all leading blanks |
| NCHAR | Return the Unicode character with the specified integer code, as defined by the Unicode standard |
| PATINDEX | Returns the starting position of the first occurrence of a pattern in a string |
| QUOTENAME | Returns a Unicode string with the delimiters added to make the input string a valid delimited identifier |
| REPLACE | Replace all occurrences of a substring, within a string, with another substring |
| REPLICATE | Return a string repeated a specified number of times |
| REVERSE | Return the reverse order of a character string |
| RIGHT | Extract a given a number of characters from a character string starting from the right |
| RTRIM | Return a new string from a specified string after removing all trailing blanks |
| SOUNDEX | Return a four-character (SOUNDEX) code of a string based on how it is spoken |
| SPACE | Returns a string of repeated spaces |
| STR | Returns character data converted from numeric data |
| STRING_AGG | Concatenate rows of strings with a specified separator into a new string |
| STRING_ESCAPE | Escapes special characters in a string and returns a new string with escaped characters |
| STRING_SPLIT | A table-valued function that splits a string into rows of substrings based on a specified separator |
| STUFF | Delete a part of a string and then insert another substring into the string starting at a specified length |
| SUBSTRING | Extract a substring within a string starting from a specified location with a specified length |
| TRANSLATE | Replace several single-characters, one-to-one translation in one operation. |
| TRIM | Return a new string from a specified string after removing all leading and trailing blanks |
| UNICODE | Returns the integer value, as defined by the Unicode standard of a character |
| UPPER | Convert a string to uppercase |
These are just a few examples of the string functions available in SQL Server. Each function has specific syntax and usage requirements, which can be found in the SQL Server documentation for the corresponding version of the software.