0

I have CrateDb version 3.2.7 running under Windows Server 2012. I create a table like this:

create table test3 (firstcolumn bigint primary key, secondcolumn int, thirdcolumn timestamp, fourthcolumn double, fifthcolumn double, sixtcolumn smallint, seventhcolumn double, heightcolumn int, ninthcolumn smallint, tenthcolumn smallint) clustered into 12 shards with(number_of_replicas = 0, refresh_interval =0);

So I'm expecting the firstcolumn to be the first, and so on. But after the creation, when I do a SELECT * FROM test3, I get the following result:

enter image description here

It seems that the first column returned is the "fifth" Looks like columns are returned in alphabetical order.

enter image description here

Does it means that CrateDB created the columns in that order? Does it keeps the order somewhere? If columns are in alphabetical order, does that mean that if I want to COPY data from another dbms to CrateDB, then I have to export data based on alphabetical order?

Danielle Paquette-Harvey
  • 1,691
  • 1
  • 16
  • 31

1 Answers1

1

For insert not necessarily, only if they are omitted do they have to be in an alphabetical order see here. Order doesn't seem to be "kept" anywhere per se.

COPY FROM is a different kind of import tactic and not quite what the good old INSERT would do. I would suggest writing a command line app to import data into cratedb. COPY FROM doesn't do any type checking, nor does it cast types and will always import the data as it was in the source file (see here). From your other question I see you may have gps related data (?) you will need to manually map them to a GEO_POINT type just as 1 example.

Crate offers good performance (whatever that means to you or me) with bulk endpoint

metase
  • 1,169
  • 2
  • 16
  • 29
  • Do you know about the bulk endpoint? Do you know how to pass a "NULL" value for a column to the bulk endpoint? I can insert data with bulk, but only if data is not null, when I specify NULL it fails. – Danielle Paquette-Harvey May 15 '19 at 18:42
  • 1
    probs not the best place to ask but just pass null in place where the argument would be. "bulk_args":[[null,"2019-4-15"],["2019-4-15","2019-4-15"]]}. – metase May 15 '19 at 22:20
  • Thanks :-) I contacted the support anyway, I'll see what they answer, I'll post it here if it's different – Danielle Paquette-Harvey May 16 '19 at 13:47