olap

In Big Query there is a function array_concat_agg that aggregates array fields by concatenating the arrays. In Snowflake there is a flatten function that can unnest nested arrays into single array. I am looking for similar functionality in duckdb.

select flatten([[1, 2], [2, 3], [4, 5]] would return [1, 2, 2, 3, 4, 5]
I would also need a distinct option:
`select flatten(DISTINCT [[1, 2],

Search before asking

• I had searched in the issues and found no similar issues.

Description

As title.

In BE, there are some many Substitute stringstream, we can replace them with fmt/format

Solution

No response

Are you willing to submit PR?

• Yes I am willing to submit a PR

Summary

Add a new handler for PromQL:
https://docs.rs/promql/latest/promql/
https://prometheus.io/docs/prometheus/latest/querying/basics/
https://promlabs.com/blog/2021/10/14/promql-vendor-compatibility-round-three

Use case:

PosgreSQL client compatibility (e.g. Trino)
SQL compliance

CrateDB

CREATE TABLE doc.x (txt TEXT)
SELECT crate.doc.x.txt FROM crate.doc.x

PostgreSQL

postgres=# CREATE TABLE public.x (txt TEXT);
CREATE TABLE
postgres=# SELECT postgres.public.x.txt FROM postgres.public.x;
 txt 
-----
(0 rows)

[From PostgreSQL docs](https://www.postg

Enhancement

CREATE TABLE t_tf (
    a int not null,
    b float,
    c1 varchar(100)
) DUPLICATE KEY (id)
DISTRIBUTED BY HASH(id) BUCKETS 1;

To create a table as above, but id does not exist.
However, the error message is:
ERROR 1064 (HY000) at line 1: Key columns should be a ordered prefix of the schema.

1. the message is not correct.
2. it should display the

Hey everyone!

mapd-core-cpu is already available on conda-forge (https://anaconda.org/conda-forge/omniscidb-cpu)

now we should add some instructions on the documentation.

at this moment it is available for linux and osx.

some additional information about the configuration:

1. for now, always install omniscidb-cpu inside a conda environment (also it is a good practice), eg:

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

Datafusion supports a few date parts like "year" or "seconds" in the EXTRACT operator.

Postgres offers a few more. In particular it offers an EPOCH date part which extracts the number of seconds since 1970-01-01 00:00:00-00 (can be negative).

See https://www.postgresql.org/docs/8

Is there an existing issue for the same feature request?

• I have checked the existing issues.

Is your feature request related to a problem?

Several showcase SQL requires the support of this function:


select DATE_FORMAT(b.measurement_time,'%Y-%m-%d') 

select DATE_FORMAT(FROM_UNIXTIME(tm.create_time), %Y%m%d)

Describe the feature you'd like

Search before asking

• I had searched in the issues and found no similar optimization requirement.

Description

Translate the README.md and README.en-US.md into English

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's [Code of Conduct](h

If we find distinct value statistics is very small compared with row counts, we can use RLE encoding when building RowSets.

https://github.com/risinglightdb/risinglight/blob/65372ee4da36bada718a6ab00cdba865ba554e5e/src/storage/secondary/compactor.rs#L93-L96