I am running into something that appears to be a global BigQuery issue that started maybe only a few days ago. It was definitely working on Jan 7th 2019. I narrowed down the issue to a simple SELECT * FROM TABLE which throws a Cannot read field 'records' of type INT64 as UINT64. The records field is declared as INTEGER in the schema and the table is a result of an aggregate query.
I am getting the same error both programmatically as well as in BigQuery UI.
If I explicitly list STRING fields, the query works. As soon as I reference records which is INTEGER, the query fails.
Job id is dulcet-outlook-94110:US.bquxjob_5883645e_16858aba0ae.
Alternatively, everyone can reproduce this using public data by saving the following query into a temp table and then doing a simple SELECT * from temp.
SELECT state, count(*) cnt FROM [bigquery-public-data:samples.natality]
group by state
This gives a slightly different but essentially the same error: Type mismatch for column 'cnt' in table temp. Expected type 'uint64', actual type 'int64' in file :mdb=cloud-dataengine.
(EDIT: Make sure to use "Allow Large Results" otherwise it will work fine).
Thank you for raising this up. This is indeed a bug in BigQuery, a fix has been completely rolled out now.
For the broken tables, although data is not lost, they have an inconsistent state with the schema. So please try to regenerate them if you can, as for now their schemas won't automatically fix themselves yet. We are working on ways to fix the schema of the existing affected tables, but it might take some time.
If you still have any problem feel free to report to the public issue tracker wpfwannabe created above.
Related
In the bigquery console, when creating a table, there used to be type JSON as an option for the column types but weirdly enought it was never present in their docs We used this column type in our production tables, and discovered later on that you can't select it in queries otherwise bigquery throws an error, and the json functions also didn't work with it. So we simply stopped using this column in the queries but they still exist in our tables.
However, in the past couple of days, all queries against this table are failing with this error 400 Json is not enabled for current project. and this column type is not present in the bigquery console anymore. It seems it was removed or deprecated? I checked the release notes, but the latest release was way before the error occured. This broke our production environment, and we couldnt even export the data because exporting gave the same error. Instead we had to use a new table without this column which meant we lost all our history.
Did anyone face the same problem with any other column types before, is it normal that a type is deprecated without users being notified beforehand. This is making me question the reliability of bigquery.
Please reach out to Google Cloud support and we will help you fix your issue with that problematic table. You may also want to try fixing it yourself using the ALTER TABLE DROP COLUMN statement that is currently in public preview [1]. This will drop the erroneous column (the data in that column only will be lost). The rest of the data will remain usable.
[1] https://cloud.google.com/bigquery/docs/reference/standard-sql/data-definition-language#alter_table_drop_column_statement
I ran into the same error message few days ago and was surprised to read about this policy change that's not backed up by a mitigation process. My attempt to use Vlad Grachev suggestion to drop this column did not prevail, as the console does not allow to query this table (same "Json is not enabled for current project." error).
My only remediation at this point is:
build a new table where the json column is switched to type string
create a pipeline that transforms the objects to strings
migrate the data through the pipeline to the new table
In BigQuery Json data can be stored in a column type "Record.Are you referring the same by JSON column type?
BigQuery uses the RECORD (or STRUCT) type to represent nested structure. A column of RECORD type is in fact a large column containing multiple child columns. For more information Refer the link below,
Json Data in BigQuery
if you are not refering to the Record Data type, The Json Column type might be a test feature that might not dependent on deprecation scheme
I'm new with Airflow and I'm currently stuck on an issue with the Bigquery operator.
I'm trying to execute a simple query on a table from a given dataset and copy the result on a new table in the same dataset. I'm using the bigquery operator to do so, since according to the doc the 'destination_dataset_table' parameter is supposed to do exactly what I'm looking for (source:https://airflow.apache.org/docs/stable/_api/airflow/contrib/operators/bigquery_operator/index.html#airflow.contrib.operators.bigquery_operator.BigQueryOperator).
But instead of copying the data, all I get is a new empty table with the schema of the one I'm querying from.
Here's my code
default_args = {
'owner':'me',
'depends_on_past':False,
'start_date':datetime(2019,1,1),
'end_date':datetime(2019,1,3),
'retries':10,
'retry_delay':timedelta(minutes=1),
}
dag = DAG(
dag_id='my_dag',
default_args=default_args,
schedule_interval=timedelta(days=1)
)
copyData = BigQueryOperator(
task_id='copyData',
dag=dag,
sql=
"SELECT some_columns,x,y,z FROM dataset_d.table_t WHERE some_columns=some_value",
destination_dataset_table='dataset_d.table_u',
bigquery_conn_id='something',
)
I don't get any warnings or errors, the code is running and the tasks are marked as success. It does create the table I wanted, with the columns I specified, but totally empty.
Any idea what I'm doing wrong?
EDIT: I tried the same code on a much smaller table (from 10Gb to a few Kb), performing a query with a much smaller result (from 500Mb to a few Kb), and it did work this time. Do you think the size of the table/the query result matters? Is it limited? Or does performing a too large query cause a lag of some sort?
EDIT2: After a few more tests I can confirm that this issue is not related to the size of the query or the table. It seems to have something to do with the Date format. In my code the WHERE condition is actually checking if a date_column = 'YYYY-MM-DD'. When I replace this condition with an int or string comparison it works perfectly. Do you guys know if Bigquery uses a particular date format or requires a particular syntax?
EDIT3: Finally getting somewhere: When I cast my date_column as a date (CAST(date_column AS DATE)) to force its type to DATE, I get an error that says that my field is actually an int-32 (Argument type mismatch). But I'm SURE that this field is a date, so that implies that either Bigquery stores it as an int while displaying it as a date, or that the Bigquery operator does some kind of hidden type conversion while loading tables. Any idea on how to fix this?
I had a similar issue when transferring data from other data sources than big-query.
I suggest casting the date_column as follows: to_char(date_column, 'YYYY-MM-DD') as date
In general, I have seen that big-query auto detection schema is often problematic. The safest way is to always specify schema before executing its corresponding query, or use operators that support schema definition.
I have a project where I was previously creating tables on Insert. I am attempting to instead perform an insertAll with a templateSuffix. It seems to work great with new tables, but I have this odd case.
The following URL (https://gist.github.com/dovy/b5b5b25e660ac037aaa130294ab42e3a) provides an example insert. I have some data from a source, the desired table (table_schema.txt) and a template schema (table_template_schema.txt). The only difference between the two schemas is the order of the last 2 columns:
|- cache_file: string
|- deduped: integer
The error I get is
HttpError:
https://www.googleapis.com/bigquery/v2/projects/flash-student-96619/datasets/log_data_v7/tables/day/insertAll?alt=json
returned "Provided Schema does not match Table
flash-student-96619:log_data_v7.day20160423. Template and generated
table schemas are incompatible"
Is insertAll really that picky? There's no way to re-order columns unless I do a query and replace on the same table. That seems incredibly painful.
Any clues from anyone out there?
I ended up doing a standard insert without tableSuffix and if it failed (try/catch) I did a insert with tableSuffix. That bypasses this insane requirement of perfect order and all works for me.
Just wish I didn't have to get around this.
I am getting an error message when I query a specific table in my data set that has a nullable timestamp field. In the BigQuery web tool, I run simple query, e.g.:
SELECT * FROM [reztrack.201401] LIMIT 100
The result I get is: Error: Schema changed for Timestamp field date
Example Job ID: esiteisthebomb:job_6WKi7ZhSi8D_Ewr8b5rKV-a5Eac
This is the exact same issue that was noted here: Error: Schema changed for Timestamp field.
Also logged this under: https://code.google.com/p/google-bigquery/issues/detail?id=307 but I was unsure since it said we should be logging everything in Stackoverlfow.
Any information on how to fix this for this or other tables would be greatly appreciated.
Note: The original answer states to contact google support, but Google support for BigQuery was moved to StackOverflow. Therefore I assume that means to open it as a new question in hopes the engineers will respond.
BigQuery recently improved the representation of its internal timestamp format (there had previously been a lot of cases where timestamps broke in strange ways and this change should fix that). Your table still was using the old timestamp format, and you tickled a bug in the old format when schemas changed (in this case, the field went from REQUIRED to OPTIONAL).
We have an automated process that coalesces tables to make their storage more efficient. I scheduled this to run over your table, and have verified that it has rewritten your table using the new timestamp format.
You should now be able to query this field of your table without further problems.
Situation:
I'm doing some penetration testing for a friend of mine and have total clearance to go postal on a demo environment. Reason for this is because I saw a XSS-hole in his online ASP-application (error page with error as param allowing html).
He has a Access DB and because of his lack of input-validation I came upon another hole: he allows sql injection in a where-clause.
I tried some stuff from:
http://www.krazl.com/blog/?p=3
But this gave limited result:
MSysRelationships is open, but his Objects table is shielded.
' UNION SELECT 1,1,1,1,1,1,1,1,1,1 FROM MSysRelationships WHERE '1' = '1 <-- worked so I know the parent table has at least 9 columns. I don't know how I can exploit the relation table to get tablenames ( I can't find any structures explanation so I don't know on what to select.
Tried brute-forceing some tablenames, but to no avail.
I do not want to trash his DB, but I do want to point out the serious flaw with some backing.
Anyone has Ideas?
Usually there are two ways to proceed from here. You could try to guess table names by the type of data which is stored in them which often works ("users" usually stores the user data ...). The other method would be to generate speaking error messages in the application to see if you can fetch table or column names from there.