SOUNDEX

Generates the Soundex code for a string.

• A Soundex code consists of a letter followed by three numerical digits. TiDB Cloud Lake's implementation returns more than 4 digits, but you can SUBSTR the result to get a standard Soundex code.
• All non-alphabetic characters in the string are ignored.
• All international alphabetic characters outside the A-Z range are ignored unless they're the first letter.

See also: SOUNDS LIKE

Syntax

SOUNDEX(<str>)

Arguments

Return Type

Returns a code of type VARCHAR or a NULL value.

Examples

SELECT SOUNDEX('Datalake');

---
D42

-- All non-alphabetic characters in the string are ignored.
SELECT SOUNDEX('Datalake!');;

---
D42

-- All international alphabetic characters outside the A-Z range are ignored unless they're the first letter.
SELECT SOUNDEX('Datalake，你好');

---
D42

SELECT SOUNDEX('你好，Datalake');

---
你342

-- SUBSTR the result to get a standard Soundex code.
SELECT SOUNDEX('Datalake Cloud'),SUBSTR(SOUNDEX('Datalake Cloud'),1,4);

soundex('datalake cloud')|substring(soundex('datalake cloud') from 1 for 4)|
-------------------------+-------------------------------------------------+
D42243                   |D422                                             |

SELECT SOUNDEX(NULL);
+-------------------------------------+
| `SOUNDEX(NULL)`                     |
+-------------------------------------+
| <null>                              |
+-------------------------------------+