Add Cursor.describe to retrieve the schema of a query

[mdesmet]

Description

Non-technical explanation

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* Fix some things. ({issue}`issuenumber`)

[hovaesco]

what is type_size?

[mdesmet]

I'm not exactly sure it is returned by DESCRIBE OUTPUT

❯ trino
trino> prepare test FROM select * from tpch.tiny.customer;
PREPARE
trino> describe output test;
 Column Name | Catalog | Schema |  Table   |     Type     | Type Size | Aliased
-------------+---------+--------+----------+--------------+-----------+---------
 custkey     | tpch    | tiny   | customer | bigint       |         8 | false
 name        | tpch    | tiny   | customer | varchar(25)  |         0 | false
 address     | tpch    | tiny   | customer | varchar(40)  |         0 | false
 nationkey   | tpch    | tiny   | customer | bigint       |         8 | false
 phone       | tpch    | tiny   | customer | varchar(15)  |         0 | false
 acctbal     | tpch    | tiny   | customer | double       |         8 | false
 mktsegment  | tpch    | tiny   | customer | varchar(10)  |         0 | false
 comment     | tpch    | tiny   | customer | varchar(117) |         0 | false
(8 rows)

Query 20221214_180638_00003_8aypw, FINISHED, 1 node
Splits: 1 total, 1 done (100,00%)
0,72 [0 rows, 0B] [0 rows/s, 0B/s]

[hovaesco]

Looks good to me.

[hashhar]

LGTM

Looks useful. Similar to ResultSetMetaData from JDBC land.