RETENTION

RETENTION

RETENTION

Description

Syntax

retention(event1, event2, ... , eventN);

The retention function takes as arguments a set of conditions from 1 to 32 arguments of type UInt8 that indicate whether a certain condition was met for the event. Any condition can be specified as an argument.

The conditions, except the first, apply in pairs: the result of the second will be true if the first and second are true, of the third if the first and third are true, etc.

Arguments

event — An expression that returns a UInt8 result (1 or 0).

Returned value

The array of 1 or 0.

1 — Condition was met for the event.

0 — Condition wasn’t met for the event.

example

DROP TABLE IF EXISTS retention_test;

CREATE TABLE retention_test(
                `uid` int COMMENT 'user id', 
                `date` datetime COMMENT 'date time' 
                )
DUPLICATE KEY(uid) 
DISTRIBUTED BY HASH(uid) BUCKETS 3 
PROPERTIES ( 
    "replication_num" = "1"
); 

INSERT into retention_test (uid, date) values (0, '2022-10-12'),
                                        (0, '2022-10-13'),
                                        (0, '2022-10-14'),
                                        (1, '2022-10-12'),
                                        (1, '2022-10-13'),
                                        (2, '2022-10-12'); 

SELECT * from retention_test;

+------+---------------------+
| uid  | date                |
+------+---------------------+
|    0 | 2022-10-14 00:00:00 |
|    0 | 2022-10-13 00:00:00 |
|    0 | 2022-10-12 00:00:00 |
|    1 | 2022-10-13 00:00:00 |
|    1 | 2022-10-12 00:00:00 |
|    2 | 2022-10-12 00:00:00 |
+------+---------------------+

SELECT 
    uid,     
    retention(date = '2022-10-12')
        AS r 
            FROM retention_test 
            GROUP BY uid 
            ORDER BY uid ASC;

+------+------+
| uid  | r    |
+------+------+
|    0 | [1]  | 
|    1 | [1]  |
|    2 | [1]  |
+------+------+

SELECT 
    uid,     
    retention(date = '2022-10-12', date = '2022-10-13')
        AS r 
            FROM retention_test 
            GROUP BY uid 
            ORDER BY uid ASC;

+------+--------+
| uid  | r      |
+------+--------+
|    0 | [1, 1] |
|    1 | [1, 1] |
|    2 | [1, 0] |
+------+--------+

SELECT 
    uid,     
    retention(date = '2022-10-12', date = '2022-10-13', date = '2022-10-14')
        AS r 
            FROM retention_test 
            GROUP BY uid 
            ORDER BY uid ASC;

+------+-----------+
| uid  | r         |
+------+-----------+
|    0 | [1, 1, 1] |
|    1 | [1, 1, 0] |
|    2 | [1, 0, 0] |
+------+-----------+

keywords

RETENTION