Function that converts multi-row values ​​into one row in sql

The function in SQL that converts multiple rows of values ​​into one row is ARRAY_TO_STRING(), which converts an array into a comma-separated string. Used in conjunction with aggregate functions such as GROUP_CONCAT(), data from multiple rows can be grouped and converted into a single row.

Function in SQL to convert multi-row values ​​into one row

Question: How Convert multi-row values ​​to one row in SQL?

Answer: You can use the SQL function ARRAY_TO_STRING() to convert multiple rows of values ​​into a single row of strings.

Detailed answer:

ARRAY_TO_STRING() function converts an array into a comma-separated string. This function can be used in conjunction with other aggregate functions such as GROUP_CONCAT() to group and convert data from multiple rows into a single row.

Syntax:

<code>ARRAY_TO_STRING(array_column, separator)</code>

Where:

• array_column: The array column to be converted to a string.
• separator: Optional, the character used to separate string elements (default is comma).

Example:

Suppose we have a table called "students" with the following columns:

id	name
1	Alice
2	Bob
3	Carol

You can use the following query to list the student names Convert to a comma separated string:

<code>SELECT ARRAY_TO_STRING(name, ', ') AS student_names
FROM students;</code>

Output:

student_names

Alice, Bob, Carol

Similarly, the following query separates student names with semicolons:

<code>SELECT ARRAY_TO_STRING(name, '; ') AS student_names
FROM students;</code>

Output:

student_names

Alice; Bob; Carol

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