How to create temporary table in Google BigQuery

2018 update - definitive answer with DDL

With BigQuery's DDL support you can create a table from the results a query - and specify its expiration at creation time. For example, for 3 days:

#standardSQL
CREATE TABLE `fh-bigquery.public_dump.vtemp`
OPTIONS(
  expiration_timestamp=TIMESTAMP_ADD(CURRENT_TIMESTAMP(), INTERVAL 3 DAY)
) AS
SELECT corpus, COUNT(*) c
FROM `bigquery-public-data.samples.shakespeare`
GROUP BY corpus

• Docs: https://cloud.google.com/bigquery/docs/data-definition-language

2019 update -- With BigQuery scripting, CREATE TEMP TABLE is officially supported. See public documentation here.

CREATE TEMP TABLE Example
(
  x INT64,
  y STRING
);

INSERT INTO Example
VALUES (5, 'foo');

INSERT INTO Example
VALUES (6, 'bar');

SELECT *
FROM Example;

To create a temporary table, use the TEMP or TEMPORARY keyword when you use the CREATE TABLE statement and use of CREATE TEMPORARY TABLE requires a script , so its better to start with begin statement.

Begin CREATE TEMP TABLE <table_name> as select * from <table_name> where <condition>; End ;

Example of creating temp tables in GCP bigquery

CREATE TABLE  `project_ID_XXXX.Sales.superStore2011` 
OPTIONS(
  expiration_timestamp=TIMESTAMP_ADD(CURRENT_TIMESTAMP(), INTERVAL 1 DAY)
) AS
SELECT 
  Product_Name,Product_Category, SUM(profit) Total_Profit,  FORMAT_DATE("%Y",Order_Date) AS Year
FROM 
  `project_ID_XXXX.Sales.superStore` 
WHERE
  FORMAT_DATE("%Y",Order_Date)="2011"
GROUP BY 
  Product_Name,Product_Category,Order_Date
ORDER BY 
   Year, Total_Profit DESC
LIMIT 5 

It's 2022, and if you type the codes to create a TEMP table in BQ's interactive windows, it will not work. Probably will display below error message:

Vaguely it will give you an idea that your interactive windows should be tied with some session. There is the official documentation on how to create sessions etc.,

The short and easy method for me was go to MORE menu of the Google BigQuery Interactive windows, select Query Settings

It will display below SS (as of 2022 April)

Enable/click Use session mode and SAVE. That's it enjoy your Temporary Tables :D

I followed Google's official document while learning UDF and encountered the issue: use of create temporary table requires a script or session

Erroneous script:

CREATE TEMP TABLE users
AS  SELECT 1 id, 10 age
UNION ALL SELECT 2, 30
UNION ALL SELECT 3, 10;

Solution:

BEGIN
    CREATE TEMP TABLE users
    AS  SELECT 1 id, 10 age
    UNION ALL SELECT 2, 30
    UNION ALL SELECT 3, 10;
END;

To create and store your data on the fly, you can specify optional _SESSION qualifier to create temporary table.

CREATE TEMP TABLE _SESSION.tmp_01
AS
 SELECT name FROM `bigquery-public-data`.usa_names.usa_1910_current
 WHERE year = 2017 
;

Here you can create the table from a complex query starting after 'AS' and the temporary table will be created at once and will be deleted after 24 hours.

To access the table,

select * from _SESSION.tmp_01;

Update September 2022:

As per the documentation, you can create a temporary table like:

    CREATE TEMP TABLE continents(name STRING, visitors INT64)
    AS
     select  geo.continent, count(distinct user_pseudo_id)  as Continent_Visitors
    FROM `firebaseProject.dataset.events_date`
    group by geo.continent order by Continent_Visitors desc;
    SELECT * from continents;
Drop table continents;