The Basics of SQL Server String Functions and their Primary Keyword(s)
When it comes to SQL Server, string functions are a fundamental part of the language used to create, manipulate and retrieve data. String functions allow you to perform various operations on character strings such as searching, replacing, concatenating, or extracting parts of a string.
1. ASCII
Retrieves the ASCII code value of a specific character.
The syntax is:
SELECT ASCII('A'); -- This will return 65.2. CHAR
Converts an ASCII value to its corresponding character.
The syntax is:
SELECT CHAR(65); -- This will return A.3. CHARINDEX
Searches a substring from a given string and returns its starting position.
The syntax is:
SELECT CHARINDEX('world', 'Hello world'); -- This will return 6.4. CONCAT
Concatenates two or more strings into a single string.
The syntax is:
SELECT CONCAT('The', ' ', 'quick', ' ', 'brown', ' ', 'fox'); -- This will return 'The quick brown fox'.5. CONCAT_WS
Concatenates multiple strings with a specific separator.
The syntax is:
SELECT CONCAT_WS(',', 'apple', 'orange', 'banana'); -- This will return 'apple,orange,banana'.6. DIFFERENCE
Compares two SOUNDEX values and returns an integer value indicating the difference.
The syntax is:
SELECT DIFFERENCE('SMITH', 'SMYTHE'); -- This will return 4.7. FORMAT
Formats a numeric value into a specific format.
The syntax is:
SELECT FORMAT(1234567.8923, 'C', 'en-US'); -- This will return $1,234,567.89.8. LEFT
Retrieves a specified number of characters from the left side of a string.
The syntax is:
SELECT LEFT('Hello world', 5); -- This will return 'Hello'.9. LEN
Returns the length of a specified string in characters.
The syntax is:
SELECT LEN('Hello world'); -- This will return 11.10. LOWER
Converts a string to lowercase.
The syntax is:
SELECT LOWER('Hello world'); -- This will return 'hello world'.11. LTRIM
Removes leading blanks from a given string.
The syntax is:
SELECT LTRIM(' Hello world'); -- This will return 'Hello world'.12. NCHAR
Returns a Unicode character based on an integer code.
The syntax is:
SELECT NCHAR(8364); -- This will return €.13. PATINDEX
Searches a string for a pattern and returns its starting position.
The syntax is:
SELECT PATINDEX('%world%', 'Hello world'); -- This will return 6.14. QUOTENAME
Adds delimiters to a specified Unicode string to create a valid delimited identifier.
The syntax is:
SELECT QUOTENAME('dbo.MyTable'); -- This will return [dbo].[MyTable].15. REPLACE
Replaces all occurrences of a substring in a given string with another string.
The syntax is:
SELECT REPLACE('Hello universe', 'universe', 'world'); -- This will return 'Hello world'.16. REPLICATE
Repeats a given string a specified number of times.
The syntax is:
SELECT REPLICATE('Ha', 5); -- This will return 'HaHaHaHaHa'.17. REVERSE
Reverses the order of the characters in a string.
The syntax is:
SELECT REVERSE('Hello world'); -- This will return 'dlrow olleH'.18. RIGHT
Retrieves a specified number of characters from the right side of a string.
The syntax is:
SELECT RIGHT('Hello world', 5); -- This will return 'world'.19. RTRIM
Removes trailing blanks from a given string.
The syntax is:
SELECT RTRIM('Hello world '); -- This will return 'Hello world'.20. SOUNDEX
Returns a four-character SOUNDEX code based on a spoken string.
The syntax is:
SELECT SOUNDEX('Hello world'); -- This will return H464.21. SPACE
Returns a specified number of repeated spaces.
The syntax is:
SELECT SPACE(3) + 'world'; -- This will return ' world'.22. STR
Converts numeric data to character data.
The syntax is:
SELECT STR(123.45, 6, 2); -- This will return '123.45'.23. STRING_AGG
Concatenates rows of strings with a specified separator.
The syntax is:
SELECT STRING_AGG('fruit', ', ') WITHIN GROUP (ORDER BY 'fruit_id'); -- This will return 'fruit1, fruit2, fruit3'.24. STRING_ESCAPE
Escapes special characters in a given string.
The syntax is:
SELECT STRING_ESCAPE('', 'html'); -- This will return '<Hello&World>'. 25. STRING_SPLIT
Splits a string into a table of substrings based on a specified separator.
The syntax is:
SELECT value FROM STRING_SPLIT('apple,orange,banana', ','); -- This will return a table with three rows containing 'apple', 'orange', and 'banana' respectively.26. STUFF
Deletes a specified length of characters from a given string and replaces it with another string.
The syntax is:
SELECT STUFF('Hello world', 6, 5, 'universe'); -- This will return 'Hello universe'.27. SUBSTRING
Retrieves a specified portion of a string.
The syntax is:
SELECT SUBSTRING('Hello world', 7, 5); -- This will return 'world'.28. TRANSLATE
Replaces specific characters in a given string with a single character.
The syntax is:
SELECT TRANSLATE('Hello, world', ', ', ';_'); -- This will return 'Hello;_world'.29. TRIM
Removes leading and trailing blanks from a given string.
The syntax is:
SELECT TRIM(' Hello world '); -- This will return 'Hello world'.30. UNICODE
Returns the integer value of a specified Unicode character.
The syntax is:
SELECT UNICODE(''); -- This will return 8364.Conclusion
In conclusion, SQL Server string functions are widely used in the everyday life of a database developer. They help to manipulate and manipulate strings by performing various functions such as searching, splitting, and concatenating.
In this article, we have discussed some of the most common SQL Server string functions along with their primary keyword(s) and uses. These functions can be used to achieve various goals and achieve a desired result, all while saving time and effort.
In this article, we have explored some of the most common SQL Server string functions and their primary keyword(s). These functions can perform various operations on character strings such as searching, replacing, concatenating, and extracting parts of a string.
By using these functions, a database developer can manipulate character strings with ease, saving time and effort. From the ASCII and CHAR functions to the STRING_SPLIT and TRANSLATE functions, we have seen how to use them and what benefits they provide.
SQL Server string functions are essential for any developer working with databases, and understanding them is essential to improve productivity.