can not count distinct in scyllaDB?

[max19950618@gmail.com]

hello everyone

I met a question about scylladb.

today I want to count distinct multiple partition key , but it seems not work for me.

For example.

 app_id | env_id | uid

--------+--------+-------------

      1 |      2 | 987g6h89183

      1 |      4 | 987g6h89183

I want to count distinct uid in scylla. 

By rights, it will return value equals to '1'. but it can not work.

thus , I want to check if can count distinct in scyllaDB.

Thank you.

Max

[Tzach Livyatan]

Hi Max

The SELECT command does include DISTINCT[1], but I'm not sure it fits your needs.

Can you please share the full example, including the schema (CREATE TABLE) and CQL query?

THanks

Tzach

[1] https://docs.scylladb.com/getting-started/dml/#select-statement

--
You received this message because you are subscribed to the Google Groups "ScyllaDB users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to scylladb-user...@googlegroups.com.
To post to this group, send email to scyllad...@googlegroups.com.
Visit this group at https://groups.google.com/group/scylladb-users.
To view this discussion on the web visit https://groups.google.com/d/msgid/scylladb-users/24f8cb51-e88b-4d6f-83c3-c2f8c06fa476%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[max19950618@gmail.com]

hi Tzach

For example:

(table schema)

```

app_id int,

env_id int,

uid text,

ts int,

PRIMARY KEY ((app_id,env_id,uid),ts)

```

following CQL command is my need ideally:

```

SELECT COUNT(DISTINCT app_id,env_id,uid) FROM table WHERE app_id=1 AND env_id=2 ALLOW FILTERING;

```

By rights, it will return '1'. But it can not work.


Tzach Livyatan於 2019年6月17日星期一 UTC+8下午3時24分09秒寫道：

Hi Max

The SELECT command does include DISTINCT[1], but I'm not sure it fits your needs.

Can you please share the full example, including the schema (CREATE TABLE) and CQL query?

THanks

Tzach

[1] https://docs.scylladb.com/getting-started/dml/#select-statement

On Mon, Jun 17, 2019 at 7:37 AM <max19...@gmail.com> wrote:

hello everyone

I met a question about scylladb.

today I want to count distinct multiple partition key , but it seems not work for me.

For example.

 app_id | env_id | uid

--------+--------+-------------

      1 |      2 | 987g6h89183

      1 |      4 | 987g6h89183

I want to count distinct uid in scylla. 

By rights, it will return value equals to '1'. but it can not work.

thus , I want to check if can count distinct in scyllaDB.

Thank you.

Max

--
You received this message because you are subscribed to the Google Groups "ScyllaDB users" group.

To unsubscribe from this group and stop receiving emails from it, send an email to scyllad...@googlegroups.com.

[Tzach Livyatan]

Thanks

This syntax is indeed not supported with CQL Select

https://docs.scylladb.com/getting-started/dml/#select-statement

On Mon, Jun 17, 2019 at 10:30 AM <max19...@gmail.com> wrote:

hi Tzach

For example:

(table schema)

```

app_id int,

env_id int,

uid text,

ts int,

PRIMARY KEY ((app_id,env_id,uid),ts)

```

 

following CQL command is my need ideally:

```

SELECT COUNT(DISTINCT app_id,env_id,uid) FROM table WHERE app_id=1 AND env_id=2 ALLOW FILTERING;

```

If I understand correctly you try to count all the clustering key values in one partition

If this is the case, reading all of them and do it in the App side should be pretty efficient

 

To unsubscribe from this group and stop receiving emails from it, send an email to scylladb-user...@googlegroups.com.

To post to this group, send email to scyllad...@googlegroups.com.
Visit this group at https://groups.google.com/group/scylladb-users.

To view this discussion on the web visit https://groups.google.com/d/msgid/scylladb-users/adb2cd01-77ab-4dd3-879d-4a356f66d615%40googlegroups.com.

[max19950618@gmail.com]

OK, I got it .

Thank you. :)

Tzach Livyatan於 2019年6月17日星期一 UTC+8下午8時56分27秒寫道：