I have a DocumentDB database in Azure which I access through the CosmosDB API.
I'd like to get all the parent fields of a document with a simple query:
SELECT p.id
FROM parent p JOIN ch IN p.property1.child
WHERE CONTAINS(UPPER(ch.name), UPPER(#childName))
This query works but I get only the 'id' property. I can't use p.* (a syntax error is throwed) and probably the list will change in the future. With * I get this error: 'SELECT *' is only valid with a single input set.
It's there a way to get the whole json of parent document without the need to write the complete list of fields on the select clause?
You can instead use SELECT VALUE p FROM p JOIN ch .... This is equivalent to p.*
Related
Is there a way to tell Talend not to remove the prefix of column names especially when they are specified in the query to retrieve data from data source and keep the names mentioned in the query itself?
Thanks!
Assuming you are using the 'guess schema' feature with a query that joins some tables. Further assuming your tables have columns with the same names you run into trouble with the guessed schema. There is no way to have talend use or even know the names of the tables the colums come from, because they are part of a 'projection' and could result from transformation and/or aggregation. Thus, you'll need to help talend guessing the correct schema, which means a) you cant use the * to select all columns and b) you should assign each column an alias that hints at the table the column comes from.
So instead of select * from employee join department on employee.department_id = department.id you'd have something like select e.id as emp_id, e.name as emp_name, d.id as department_id, d.name as department_name from employee e join department d on e.department_id = d.id. The id from employee will be emp_id in the guessed schema.
I have a table with a column (value) that holds different types of information that I need to parse into separate columns. In postgresql, I can easily do this:
SELECT m1.value shipname
, m2.value agent
FROM maritimeDB m1
JOIN maritimeDB m2
ON m1.rowID = m2.rowID
AND m2.itemname = 'Agent'
WHERE m1.rowID
IN (SELECT DISTINCT rowID FROM maritimeDB WHERE entity='9999')
AND m1.itemname='shipname'
I want to do this same sort of query in BigQuery (with JOIN becoming LEFT JOIN), but I get this error:
Error: ON clause must be AND of = comparisons of one field name from each table, with all field names prefixed with table name.
Any suggestions?
This error is coming from Legacy SQL dialect (which is default). This query should work with Standard SQL dialect which supports arbitrary JOIN predicates.
SELECT pl_id,
distinct ON (store.store_ID),
in_user_id
FROM plan1.plan_copy_levl copy1
INNER JOIN plan1._PLAN_STORE store
ON copy1.PLAN_ID = store .PLAN_ID;
while running this query in postgres server i am getting the below error..How to use the distinct clause..in above code plan 1 is the schema name.
ERROR: syntax error at or near "distinct" LINE 2: distinct ON
(store.store_ID),
You are missing an order by where the first set of rows should be the ones specified in the distinct on clause. Also, the distinct on clause should be at start of the selection list.
Try this:
SELECT distinct ON (store_ID) store.store_ID, pl_id,
in_user_id
FROM plan1.plan_copy_levl copy1
INNER JOIN plan1._PLAN_STORE store
ON copy1.PLAN_ID = store .PLAN_ID
order by store_ID, pl_id;
I'm a little new to DB2, and am having trouble developing a query. I have created a user-defined function that returns a table of data which I want to then join and select from in larger select statement. I'm working on a sensitive db, so the query below isn't what I'm literally running, but it's almost exactly like it (without the other 10 joins I have to do lol).
select
A.customerId,
A.firstname,
A.lastname,
B.orderId,
B.orderDate,
F.currentLocationDate,
F.currentLocation
from
customer A
INNER JOIN order B
on A.customerId = B.customerId
INNER JOIN table(getShippingHistory(B.customerId)) as F
on B.orderId = F.orderId
where B.orderId = 35
This works great if I run this query without the where clause (or some other where clause that doesn't check for an ID). When I include the where clause, I get the following error:
Error during Prepare 58004(-901)[IBM][CLI Driver][DB2/LINUXX8664]
SQL0901N The SQL statement failed because of a non-severe system
error. Subsequent SQL statements can be processed. (Reason "Bad Plan;
Unresolved QNC found".) SQLSTATE=58004
I have tracked the issue down to fact that I'm using one of join criteria for the parameters (B.customerId). I have validated this fact by replacing B.customerId with a valid customerId, and the query works great. Problem is, I don't know the customerId when calling this query. I know only the orderId (in this example).
Any thoughts on how to restructure this so I can make only 1 call to get all the info? I know the plan is the problem b/c the customerId isn't getting resolved before the function is called.
So if I understand correctly, the function getShippingHistory(customerId) returns a table.
And if you call it with a single customer Id that table gets joined in your query above no problem at all.
But the way you have the query written above, you are asking db2 to call the function for every row returned by your query (i.e. every b.customerId that matches your join and where conditions).
So I'm not sure what behaviour you are expecting, because what you're asking for is a table back for every row in your query, and db2 (nor I) can figure out what the result is supposed to look like.
So in terms of restructuring your query, think about how you can change the getShippingHistory logic when multiple customer Ids are involved.
i found the best solution (given the current query structure) is to use a LEFT join instead of an INNER join in order force the LEFT part of the join to happen which will resolve the customerId to a value by the time it gets to the function call.
select
A.customerId,
A.firstname,
A.lastname,
B.orderId,
B.orderDate,
F.currentLocationDate,
F.currentLocation
from
customer A
INNER JOIN order B
on A.customerId = B.customerId
LEFT JOIN table(getShippingHistory(B.customerId)) as F
on B.orderId = F.orderId
where B.orderId = 35
What about the following is not proper syntax for Postgresql?
select p.*, SUM(vote) as votes_count
FROM votes v, posts p
where p.id = v.`voteable_id`
AND v.`voteable_type` = 'Post'
group by v.voteable_id
order by votes_count DESC limit 20
I am in the process of installing postgresql locally but wanted to get this out sooner :)
Thank you
MySQL is a lot looser in its interpretation of standard SQL than PostgreSQL is. There are two issues with your query:
Backtick quoting is a MySQL thing.
Your GROUP BY is invalid.
The first one can be fixed by simply removing the offending quotes. The second one requires more work; from the fine manual:
When GROUP BY is present, it is not valid for the SELECT list expressions to refer to ungrouped columns except within aggregate functions, since there would be more than one possible value to return for an ungrouped column.
This means that every column mentioned in your SELECT either has to appear in an aggregate function or in the GROUP BY clause. So, you have to expand your p.* and make sure that all those columns are in the GROUP BY, you should end up with something like this but with real columns in place of p.column...:
select p.id, p.column..., sum(v.vote) as votes_count
from votes v, posts p
where p.id = v.voteable_id
and v.voteable_type = 'Post'
group by p.id, p.column...
order by votes_count desc
limit 20
This is a pretty common problem when moving from MySQL to anything else.