The GROUP BY clause is an optional clause that can be used with the SQLite SELECT statement. It is used for coding data queries.
When applying the GROUP BY statement data rows are returned for each group. This is helpful when combined with a aggregate function. Exemplary aggregate functions in SQLite are:
- SQLite MIN
- SQLite MAX
- SQLite SUM
- SQLite COUNT
- SQLite AVG
Relevant syntax is demonstrated below:
SELECT
col_01,
MIN(col_2)
FROM
table
GROUP BY
col_01, col_02;
Now an example:
SELECT
client_id, COUNT(value)
FROM
sales
GROUP BY
client_id;