The following query was attempted to be executed when performing batch analytics with WSO2 DAS using Spark SQL. Tables 'First', 'Middle' and 'Third' are required to be combined and written to table 'All_three'.
INSERT OVERWRITE TABLE All_three
SELECT SYMBOL, VOLUME FROM First
UNION
SELECT SYMBOL, VOLUME FROM Middle
UNION
SELECT SYMBOL, VOLUME FROM Third;
Following error is displayed on WSO2 DAS when this query is executed:
ERROR: [1.79] failure: ``limit'' expected but `union' found INSERT OVERWRITE TABLE X1234_All_three SELECT SYMBOL, VOLUME FROM X1234_First UNION SELECT SYMBOL, VOLUME FROM X1234_Middle UNION SELECT SYMBOL, VOLUME FROM X1234_Third ^
Using LIMIT with UNION is not a necessity to the best of my knowledge. Enclosing the SELECT queries in parentheses too was attempted which didn't work. What am I doing wrong here? Thank you in advance!
I had the same issue.
Please make sure you had an whitespace in end of each row.
The reason is it is not considering \n as a whitespace like SSMS or other query editors.
So it reads your query without whitespace.
Hence, it read like SELECT * FROM FirstUNION not like SELECT * FROM First UNION
My issue was resolved and I hope this helps for you too.
There exists a problem with the query you mentioned here. Please change the query as below.
INSERT OVERWRITE TABLE All_three
select * from (
SELECT SYMBOL, VOLUME FROM First
UNION
SELECT SYMBOL, VOLUME FROM Middle
UNION
SELECT SYMBOL, VOLUME FROM Third
) temp;
Actually what we do here is, wrapping the union result into temporary data element called temp and select everything from there. Spark-SQL parser only takes single select element in the insert queries, and at the end of a select query it expects a limit (if available). therefore, you need to wrap the subsequent select statements into one select element. Hope this resolves your issue.
Related
I have a table with many columns let say column1,....,column20. I don't want to scroll everytime to the end of the result table to see the value of column20. In mssql I usually do
SELECT column20, * FROM TABLE but apparently this is not valid in MySQL. Any hints? (I also don't want to select all columns explicitly in the select statement)
You have to give the table name in your query, otherwise mysql complains :
SELECT column20, mytable.* FROM mytable
PS: I have absolutely no idea as to why, because SELECT *, column20 FROM mytable works just fine... Strange things happens sometimes ^^
I have a query that works when I do
SELECT DISTINCT(table.field.id), 1 FROM ...
but fails when I do
SELECT 1, DISTINCT(table.field.id) FROM ...
Is this a known behavior?
Why does the first one work while the second doesn't?
Unfortunately I'm not able to add a comment yet.
What #Gordon Linoff has written is exactly right.
You are getting error as DISTINCT in general works as part of SELECT clause or AGGREGATE function. It is used to return unique rows from a result set and it can be used to force unique column values within an aggregate function.
Examples: SELECT DISTINCT * ... COUNT(DISTINCT COLUMN) or SUM(DISTINCT COLUMN).
More information's about DISTINCT in popular DB engines:
PostgreSQL:https://www.postgresql.org/docs/9.0/static/sql-select.html#SQL-DISTINCT
SQL Server: https://www.techonthenet.com/sql_server/distinct.php
Oracle: https://www.techonthenet.com/oracle/distinct.php
MySQL:
https://dev.mysql.com/doc/refman/5.7/en/distinct-optimization.html
https://dev.mysql.com/doc/refman/5.7/en/select.html
SQL Server 2008 R2 - Query from 2014 SSMS but fails from code as well.
Strange - first reference to table B works, second fails with an 'Invalid object B' error. What am I doing wrong? GO's don't help.
WITH B as (SELECT BatchOutId, SettleMerchantCode, BatchDate, BatchStatusCode, BatchTransCnt, BatchTotAmt, BatchAdjustAmt, BatchAdjustCnt
FROM MAF01
GROUP BY BatchOutId, SettleMerchantCode, BatchDate, BatchStatusCode, BatchTransCnt, BatchTotAmt, BatchAdjustAmt, BatchAdjustCnt)
SELECT * FROM B ORDER BY BatchOutId DESC
SELECT * FROM B ORDER BY BatchOutId DESC
This is as expected.
CTEs are only in scope for the next statement. They are just named queries.
You would need to either
Repeat the definition of the CTE.
Move the definition out into a view or inline function.
Materialise the results into a temp table.
Depending on what you were expecting to happen.
A cte is only valid for one query, not an entire batch. So once you do the first SELECT * FROM B, that query is finished. The next query no longer has access to the cte that the first query used.
I know this has to be duplicate
You can have multiple CTE but only one statement
The two Select are two statements
If you use a #temp then you can have more than one statement
I cannot create a virtual table for this. Basically what I have, is a list of values:
'Succinylcholine','Thiamine','Trandate','Tridol Drip'
I want to know which of those values is not present in table1 and display them. Is this possible? I have tried using left joins and creating a variable with the list which I can compare to the table, but it returns the wrong results.
This is one of the things I have tried:
SET #list="'Amiodarone','Ammonia Inhalents','Aspirin';
SELECT #list FROM table1 where #list not in (
SELECT Description
FROM table1
);
With only narrow exceptions, you need to have data in table form to be able to obtain those data in your result set. This is the essential problem that all attempts at a solution to this problem run into, given that you cannot create a temporary table. If indeed you can provide the input in any form or format (per your comment), then you can provide it in the form of a subquery:
(
SELECT 'Amiodarone' AS description
UNION ALL
SELECT 'Ammonia Inhalents'
UNION ALL
SELECT 'Aspirin'
)
(Note that that exercises the biggest of the exceptions I noted: you can select scalars directly, without a base table. If you like, you can express that explicitly -- in MySQL and Oracle, at least -- by selecting FROM DUAL.)
In that case, this should work for you:
SELECT
a.description
FROM
(
SELECT 'Amiodarone' AS description
UNION ALL
SELECT 'Ammonia Inhalents'
UNION ALL
SELECT 'Aspirin'
) a
LEFT JOIN table1
ON a.description = table1.description
WHERE table1.description IS NULL
That won't work. the variable's contents will be treated as a monolithic string - one solid block of letters, not 3 separate comma-separated values. The query will be parsed/executed as:
SELECT ... WHERE "'Amio.....rin'" IN (x,y,z,...)
^--------------^--- string
Plus, since you're just doing a sub-select on the very same table, there's no point in this kind of a construct. You could try mysql find_in_set() function:
SELECT #list
FROM table1
WHERE FIND_IN_SET(Description, #list) <> ''
So I have joined 3 queries together using UNIONs and want to count the number of lines in the result, but it's a bit weird. It actually works, and gives the correct answer, but it doesn't assign the "AS" part correctly.
SELECT COUNT(*) FROM (
(Long Select Statement)
UNION
(AnotherLong Select Statement)
UNION
(Even Longer Select Statement)
)
AS NoOfTweets";
The outcome is correct, but instead of assigning it to "NoOfTweets" it assigns it to "Count(*)". If I remove the "AS NoOfTweets" it stops working. If I remove some brackets it stops working. I'm running low on ideas after a long day! I can post the whole code if needs be but would rather not as it's quite long and I think that bit works.
Thanks in advance, Jack.
Edit: Fixed with:
SELECT COUNT(*) NoOfTweets FROM (
(Long Select Statement)
UNION
(AnotherLong Select Statement)
UNION
(Even Longer Select Statement)
)
AS NoOfTweets";
Thanks guys :)
You aren't putting it in the correct location. The beginning of your query should look like this:
SELECT COUNT(*) AS NoOfTweets
More on Column Alias
SELECT COUNT(*) NoOfTweets FROM
(Long Select Statement)
UNION
(AnotherLong Select Statement)
UNION
(Even Longer Select Statement)
or
SELECT COUNT(*) AS NoOfTweets FROM
(Long Select Statement)
UNION
(AnotherLong Select Statement)
UNION
(Even Longer Select Statement)
You have to use AS exactly after the item you are counting:
SELECT COUNT(*) AS `NoOfTweets`
FROM ( ... )
Also be careful with the " you have near the end. Or maybe it comes from a longer string.
The error is Every derived table must have its own alias which is something I didn't know, so thanks for the education :)
http://sqlfiddle.com/#!9/d30f4/4
Nice of MySQL to give an explanation - I tried with MS SQL on SQLFiddle and just got Incorrect syntax near ')'. which isn't so helpful!
So, your 'NoOfTweets' is the name given to the results column, and also to the 'derived table' which is required by the SQL engine but could be a different name ... it's not returned in the results. The point of naming a derived table is in case you wish to JOIN to other tables and reference the fields in the joins.