STRING_AGG
Aggregate function.
The STRING_AGG() function converts all the non-NULL values of a column to String, separated by the delimiter.
Syntax
STRING_AGG(<expr>)
STRING_AGG(<expr> [, delimiter])
info
If <expr>
is not a String expression, should use ::VARCHAR
to convert.
For example:
SELECT string_agg(number::VARCHAR, '|') AS s FROM numbers(5);
+-----------+
| s |
+-----------+
| 0|1|2|3|4 |
+-----------+
Arguments
Arguments | Description |
---|---|
<expr> | Any string expression (if not a string, use ::VARCHAR to convert) |
delimiter | Optional constant String, if not specified, use empty String |
Return Type
the String type
Example
Create a Table and Insert Sample Data
CREATE TABLE programming_languages (
id INT,
language_name VARCHAR
);
INSERT INTO programming_languages (id, language_name)
VALUES (1, 'Python'),
(2, 'JavaScript'),
(3, 'Java'),
(4, 'C#'),
(5, 'Ruby');
Query Demo: Concatenate Programming Language Names with a Delimiter
SELECT STRING_AGG(language_name, ', ') AS concatenated_languages
FROM programming_languages;
Result
| concatenated_languages |
|------------------------------------------|
| Python, JavaScript, Java, C#, Ruby |