Google spreadsheet "=QUERY" join() equivalent function?

Question

This question is concerning joining two databases in Google spreadsheet using =QUERY function

I have a table like so in range A1:C3

a d g
b e h
c f i

I have another table

c j m
a k n
b l o

I want the final table to look like this

a d g k n
b e h l o 
c f i j m

I can do this by using a vlookup function pretty easily in cell D1 and paste it down and across, but my dataset is huge. I would need a whole page of vlookups and Google Spreadsheet tells I'm at my limit in complexities.

I look at the Google's Query Language reference... there doesn't seem to be an type of "join" functions mentioned. You would think it would be an easy "join on A" type operation.

Can anybody solves this without a vlookup?

Answer 1

Short answer

Google QUERY Language version 0.7 (2016) doesn't include a JOIN (LEFT JOIN) operator but this could be achieved by using an array formula which result could be used as input for the QUERY function or for other uses.

Explanation

Array formulas and the array handling features of Google Sheets make possible to make a JOIN between two simple tables. In order to make easier to read, the proposed formula use named ranges instead of range references.

Named Ranges

• table1 : Sheet1!A1:C3
• table2 : Sheet2!A1:C3
• ID : Sheet1!A1:A3

Formula

=ArrayFormula(
   {
     table1,
     vlookup(ID,table2,COLUMN(Indirect("R1C2:R1C"&COLUMNS;(table2),0)),0)
   }
)

Remarks:

• Using open ended ranges is possible but this could make the the spreadsheet slower.
• To speed up the recalculation time :
  1. Replace Indirect("R1C2:R1C"&COLUMNS(table2),0) by an array of constants from 2 to number of columns of table2.
  2. Remove the empty rows from the spreadsheet

Example

See this sheet for an example

Note

On 2017 Google improved the official help article in English about QUERY, QUERY function. It still doesn't include yet topics like this but could be helpful to understand how it works.