2

I've been trying to run this query:

SELECT
  created
FROM
  TABLE_DATE_RANGE(
      program1_insights.insights_,
      TIMESTAMP('2016-01-01'),
      TIMESTAMP('2016-02-09')
  )
LIMIT
  10

And BigQuery complains that the query is too large. I've experimented with writing the table names out manually:

SELECT
  created
FROM program1_insights.insights_20160101,
program1_insights.insights_20160102,
program1_insights.insights_20160103,
program1_insights.insights_20160104,
program1_insights.insights_20160105,
program1_insights.insights_20160106,
program1_insights.insights_20160107,
program1_insights.insights_20160108,
program1_insights.insights_20160109,
program1_insights.insights_20160110,
program1_insights.insights_20160111,
program1_insights.insights_20160112,
program1_insights.insights_20160113,
program1_insights.insights_20160114,
program1_insights.insights_20160115,
program1_insights.insights_20160116,
program1_insights.insights_20160117,
program1_insights.insights_20160118,
program1_insights.insights_20160119,
program1_insights.insights_20160120,
program1_insights.insights_20160121,
program1_insights.insights_20160122,
program1_insights.insights_20160123,
program1_insights.insights_20160124,
program1_insights.insights_20160125,
program1_insights.insights_20160126,
program1_insights.insights_20160127,
program1_insights.insights_20160128,
program1_insights.insights_20160129,
program1_insights.insights_20160130,
program1_insights.insights_20160131,
program1_insights.insights_20160201,
program1_insights.insights_20160202,
program1_insights.insights_20160203,
program1_insights.insights_20160204,
program1_insights.insights_20160205,
program1_insights.insights_20160206,
program1_insights.insights_20160207,
program1_insights.insights_20160208,
program1_insights.insights_20160209
LIMIT
  10

And not surprisingly, BigQuery returns the same error. This Q&A says that "query too large" means that BigQuery is generating an internal query that's too large to be processed. But in the past, I've run queries over way more than 40 tables with no problem.

My question is: what is it about this query in particular that's causing this error, when other, larger-seeming queries run fine? Is it that doing a single union over this number of tables is not supported?

Community
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Bryan
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1 Answers1

1

Answering question: what is it about this query in particular that's causing this error

The problem is not in query itself.
Query looks good.
I just run similar query against ~400 daily tables with total 5.8B (billion) rows of total size 5.7TB with:
Query complete (150.0s elapsed, 21.7 GB processed)

SELECT
  Timestamp
FROM
  TABLE_DATE_RANGE(
      MyEvents.Events_,
      TIMESTAMP('2015-01-01'),
      TIMESTAMP('2016-02-12')
  )
LIMIT
  10

You should look around - btw, are you sure you are not over-simplifying query in your question?

Mikhail Berlyant
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