I have a peewee query that looks like this:
toptx24h = Transaction.select(fn.MAX(Transaction.amount).alias('amount'), User.user_name).join(User,on=(User.wallet_address==Transaction.source_address)).where(Transaction.created > past_dt).limit(1)
My understanding is this should be equivalent to:
select MAX(t.amount) as amount, u.user_name from transaction t inner join user u on u.wallet_address = t.source_address where transaction.created > past_dt limit 1
My question is how to I access the results user_name and amount
When I try this, I get an error saying top has no attribute named amount
for top in toptx24h:
top.amount # No such attribute amount
I'm just wondering how i can access the amount and user_name from the select query.
Thanks
I think you need a GROUP BY clause to ensure you're grouping by User.username.
I wrote some test code and confirmed it's working:
with self.database.atomic():
charlie = TUser.create(username='charlie')
huey = TUser.create(username='huey')
data = (
(charlie, 10.),
(charlie, 20.),
(charlie, 30.),
(huey, 1.5),
(huey, 2.5))
for user, amount in data:
Transaction.create(user=user, amount=amount)
amount = fn.MAX(Transaction.amount).alias('amount')
query = (Transaction
.select(amount, TUser.username)
.join(TUser)
.group_by(TUser.username)
.order_by(TUser.username))
with self.assertQueryCount(1):
data = [(txn.amount, txn.user.username) for txn in query]
self.assertEqual(data, [
(30., 'charlie'),
(2.5, 'huey')])
Related
I'm using sqlx for the first time today.
I'm having really hard time understanding my SQL errors because I cannot copy & paste logged queries in my IDE because the parameters are not converted from placeholders.
It prints:
SELECT * from players where team_id = $1 AND id = $2
but I would like the below instead:
SELECT * from players where team_id = 'ABC' AND id = '123'
How to do this?
i have i would like to create a join over several tables.
table login : I would like to retrieve all the data from login
table logging : calculating the Nb_of_sessions for each db & for each a specific event type by user
table meeting : calculating the Nb_of_meetings for each db & for each user
table live : calculating the Nb_of_live for each db & for each user
I have those queries with the right results :
SELECT db.id,_id as userid,firstname,lastname
FROM "logins"."login",
UNNEST(dbs) AS a1 (db)
SELECT dbid,userid,count(distinct(sessionid)) as no_of_visits,
array_join(array_agg(value.from_url),',') as from_url
FROM "loggings"."logging"
where event='url_event'
group by db.id,userid;
SELECT dbid,userid AS userid,count(*) as nb_interviews,
array_join(array_agg(interviewer),',') as interviewer
FROM "meetings"."meeting"
group by dbid,userid;
SELECT dbid,r1.user._id AS userid,count(_id) as nb_chat
FROM "lives"."live",
UNNEST(users) AS r1 (user)
group by dbid,r1.user._id;
But when i begin to try put it all together, it seems i retrieve bad data (i have only on db retrieved) and it seems not efficient.
select a1.db.id,a._id as userid,a.firstname,a.lastname,count(rl._id) as nb_chat
FROM
"logins"."login" a,
"loggings"."logging" b,
"meetings"."meeting" c,
"lives"."live" d,
UNNEST(dbs) AS a1 (db),
UNNEST(users) AS r1 (user)
where a._id = b.userid AND a._id = c.userid AND a._id = r1.user._id
group by 1,2,3,4
Do you have an idea ?
Regards.
The easiest way is to work with with to structure the subquery and then reference them.
with parameter reference:
You can use WITH to flatten nested queries, or to simplify subqueries.
The WITH clause precedes the SELECT list in a query and defines one or
more subqueries for use within the SELECT query.
Each subquery defines a temporary table, similar to a view definition,
which you can reference in the FROM clause. The tables are used only
when the query runs.
Since you already have working sub queries, the following should work:
with logins as
(
SELECT db.id,_id as userid,firstname,lastname
FROM "logins"."login",
UNNEST(dbs) AS a1 (db)
)
,visits as
(
SELECT dbid,userid,count(distinct(sessionid)) as no_of_visits,
array_join(array_agg(value.from_url),',') as from_url
FROM "loggings"."logging"
where event='url_event'
group by db.id,userid
)
,meetings as
(
SELECT dbid,userid AS userid,count(*) as nb_interviews,
array_join(array_agg(interviewer),',') as interviewer
FROM "meetings"."meeting"
group by dbid,userid
)
,chats as
(
SELECT dbid,r1.user._id AS userid,count(_id) as nb_chat
FROM "lives"."live",
UNNEST(users) AS r1 (user)
group by dbid,r1.user._id
)
select *
from logins l
left join visits v
on l.dbid = v.dbid
and l.userid = v.userid
left join meetings m
on l.dbid = m.dbid
and l.userid = m.userid
left join chats c
on l.dbid = c.dbid
and l.userid = c.userid;
I am stuck with a query which takes more time in JOIN, I want to use WHERE EXISTS in place of JOIN since as performance wise EXISTS takes less time than it.
I have modified the query and it's executing as per expectation but I am not able to use sub query's columns in my main query
Here is my query
SELECT MAX(st.grade_level::integer) AS grades ,
scl.sid AS org_sourced_id
FROM schedules_53b055b75cd237fde3af904c1e726e12 sch
LEFT JOIN schools scl ON(sch.school_id=scl.school_id)
AND scl.batch_id=sch.batch_id
AND scl.client_id = sch.client_id
AND sch.run_id = scl.run_id
WHERE EXISTS
(SELECT t.term_id,t.abbreviation
FROM terms t
WHERE (sch.term = t.term_id)
AND t.batch_id=sch.batch_id
AND t.client_id = sch.client_id
AND t.run_id = sch.run_id)
AND EXISTS
(SELECT st.grade_level,
st.sid
FROM students st
WHERE (sch.student_id=st.sid)
AND st.batch_id= sch.batch_id
AND st.client_id = sch.client_id
AND st.run_id = sch.run_id)
GROUP BY scl.sid ,
sch.course_name ,
sch.course_number,
sch.school_id
And I am getting this error:
ERROR: missing FROM-clause entry for table "st"
SQL state: 42P01
Character: 29
I have only used one column here just for sample but I have to use more fields from sub query.
My main aim is that how can I achieve this with EXISTS or any alternate solution which is more optimal as performance wise
I am using pg module on Node.js since as back end I am using Node.js.
UPDATE
Query with JOIN
SELECT MAX(st.grade_level::integer) AS grades ,
scl.sid AS org_sourced_id
FROM schedules_53b055b75cd237fde3af904c1e726e12 sch
LEFT JOIN schools scl ON(sch.school_id=scl.school_id)
AND scl.batch_id=sch.batch_id
AND scl.client_id = sch.client_id
AND sch.run_id = scl.run_id
LEFT JOIN terms t ON (sch.term = t.term_id)
AND t.batch_id=sch.batch_id
AND t.client_id = sch.client_id
AND t.run_id = sch.run_id
LEFT JOIN students st ON (sch.student_id=st.sid)
AND st.batch_id= sch.batch_id
AND st.client_id = sch.client_id
AND st.run_id = sch.run_id
GROUP BY scl.sid ,
sch.course_name ,
sch.course_number,
sch.school_id
I would like to generate the query that results for the BeneficiaryID 'ABC123' along with some other inputs if they were also given. Suppose if the currency value is given, I would like to include the Currency condition as well in the JOIN query, so as well the Category. I have the following code snippet in the SOAP UI Groovy script.
query= " CORR.BeneficiaryID LIKE 'ABC123'"
if (currencyValue!=""){
query=query + " and CORR.Currency LIKE '${currencyValue}'"
}
if (CategoryValue!=""){
query=query + " and CORR.Category LIKE '${CategoryValue}'"
}
log.info("Query" + query)
Outputrows = sql.rows("select CORR.Preferred as preferred ,CORR.Category as category,CORR.Currency as currency\
from BENEFICIARY CORR \
JOIN LOCATION LOC on CORR.UID=LOC.UID and ${query}
log.info("Output rows size" + Outputrows.size())
When currency and category are not given, I would like to have the following query run and get me the results.
select CORR.Preferred as preferred ,CORR.Category as category,CORR.Currency as currency\
from BENEFICIARY CORR \
JOIN LOCATION LOC on CORR.UID=LOC.UID and CORR.BeneficiaryID LIKE 'ABC123'
and when the currency and category are given(say USD & Commercial), then the following query.
select CORR.Preferred as preferred ,CORR.Category as category,CORR.Currency as currency\
from BENEFICIARY CORR \
JOIN LOCATION LOC on CORR.UID=LOC.UID and CORR.BeneficiaryID LIKE 'ABC123' and CORR.Currency LIKE 'USD' and CORR.Category LIKE 'Commercial'
All I could see on the result for Outputrows.size() is zero(0).
Can you please correct me where am I doing wrong.
Thanks.
Here is changed script.
Since the issue to just build query, only putting that part remove sql execution part as that is not really the issue.
//Define the values or remove if you get those value from somewhere else
//Just put them here to demonstrate
//You may also try by empty value to make sure you are getting the right query
def currencyValue = 'USD'
def categoryValue = 'Commercial'
def query = 'select CORR.Preferred as preferred, CORR.Category as category,CORR.Currency as currency from BENEFICIARY CORR JOIN LOCATION LOC on CORR.UID = LOC.UID and CORR.BeneficiaryID LIKE \'ABC123\''
currencyValue ? (query += " and CORR.Currency LIKE '${currencyValue}'") : query
categoryValue ? (query += " and CORR.Category LIKE '${categoryValue}'") : query
log.info "Final query is \n ${query}"
You can just pass query to further where you need to run the sql, say sql.rows(query)
You may quickly try Demo
I have created a query with a subquery in Access, and cannot link it in Excel 2003: when I use the menu Data -> Import External Data -> Import Data... and select the mdb file, the query is not present in the list. If I use the menu Data -> Import External Data -> New Database Query..., I can see my query in the list, but at the end of the import wizard I get this error:
Too few parameters. Expected 2.
My guess is that the query syntax is causing the problem, in fact the query contains a subquery. So, I'll try to describe the query goal and the resulting syntax.
Table Positions
ID (Autonumber, Primary Key)
position (double)
currency_id (long) (references Currency.ID)
portfolio (long)
Table Currency
ID (Autonumber, Primary Key)
code (text)
Query Goal
Join the 2 tables
Filter by portfolio = 1
Filter by currency.code in ("A", "B")
Group by currency and calculate the sum of the positions for each currency group an call the result: sumOfPositions
Calculate abs(sumOfPositions) on each currency group
Calculate the sum of the previous results as a single result
Query
The query without the final sum can be created using the Design View. The resulting SQL is:
SELECT Currency.code, Sum(Positions.position) AS SumOfposition
FROM [Currency] INNER JOIN Positions ON Currency.ID = Positions.currency_id
WHERE (((Positions.portfolio)=1))
GROUP BY Currency.code
HAVING (((Currency.code) In ("A","B")));
in order to calculate the final SUM I did the following (in the SQL View):
SELECT Sum(Abs([temp].[SumOfposition])) AS sumAbs
FROM [SELECT Currency.code, Sum(Positions.position) AS SumOfposition
FROM [Currency] INNER JOIN Positions ON Currency.ID = Positions.currency_id
WHERE (((Positions.portfolio)=1))
GROUP BY Currency.code
HAVING (((Currency.code) In ("A","B")))]. AS temp;
So, the question is: is there a better way for structuring the query in order to make the export work?
I can't see too much wrong with it, but I would take out some of the junk Access puts in and scale down the query to this, hopefully this should run ok:
SELECT Sum(Abs(A.SumOfPosition)) As SumAbs
FROM (SELECT C.code, Sum(P.position) AS SumOfposition
FROM Currency As C INNER JOIN Positions As P ON C.ID = P.currency_id
WHERE P.portfolio=1
GROUP BY C.code
HAVING C.code In ("A","B")) As A
It might be worth trying to declare your parameters in the MS Access query definition and define their datatypes. This is especially important when you are trying to use the query outside of MS Access itself, since it can't auto-detect the parameter types. This approach is sometimes hit or miss, but worth a shot.
PARAMETERS [[Positions].[portfolio]] Long, [[Currency].[code]] Text ( 255 );
SELECT Sum(Abs([temp].[SumOfposition])) AS sumAbs
FROM [SELECT Currency.code, Sum(Positions.position) AS SumOfposition
FROM [Currency] INNER JOIN Positions ON Currency.ID = Positions.currency_id
WHERE (((Positions.portfolio)=1))
GROUP BY Currency.code
HAVING (((Currency.code) In ("A","B")))]. AS temp;
I have solved my problems thanks to the fact that the outer query is doing a trivial sum. When choosing New Database Query... in Excel, at the end of the process, after pressing Finish, an Import Data form pops up, asking
Where do you want to put the data?
you can click on Create a PivotTable report... . If you define the PivotTable properly, Excel will display only the outer sum.