Is it possible to chain subsequent queries's where clauses in Dapper based on the results of a previous query in the same connection? - asp.net-core-2.0

Is it possible to use .QueryMultiple (or some other method) in Dapper, and use the results of each former query to be used in the where clause of the next query, without having to do each query individually, get the id, and then .Query again, get the id and so on.
For example,
string sqlString = #"select tableA_id from tableA where tableA_lastname = #lastname;
select tableB_id from tableB WHERE tableB_id = tableA_id";
db.QueryMultiple.(sqlString, new {lastname = "smith"});
Is something like this possible with Dapper or do I need a view or stored procedure to accomplish this? I can use multiple joins for one SQL statement, but in my real query there are 7 joins, and I didn't think I should return 7 objects.
Right now I'm just using object.

You can store every previous query in table parameter and then first perform select from the parameter and query for next, for example:
DECLARE #TableA AS Table(
tableA_id INT
-- ... all other columns you need..
)
INSERT #TableA
SELECT tableA_id
FROM tableA
WHERE tableA_lastname = #lastname
SELECT *
FROM #TableA
SELECT tableB_id
FROM tableB
JOIN tableA ON tableB_id = tableA_id

Related

How to pass WHERE clause to Sequelize generated subqueries?

I have a Sequelize view that uses joins like this:
select * from tableA left join (select * from tableB where someKey={some input}) newTableB on tableA.someId = newTableB.someId
Now, when I create a view from this query, I can create a sequelize model for it. But, I want to execute the query in sequelize... like -
models.tableView.findAll({ some clause })
In the above where clause, I want to pass the value of someKey (referring to someKey={some input} in the sample view). How do I do that?
I don't want to fetch all data and then apply the tableB.someKey=something (as that will take far more time)

How can I store the value of a subquery into a variable in Hana Studio?

I would like to know how can I store the value of subquery to use it in an operation after it recieve the value. For example:
Select IDTruck
, TruckPrice = (select "TruckPrice" from "Table1" where ("TruckID" = '123'))
, TruckUnit = (select "TruckUnit" from "Table2" )
, TruckPrice * TruckUnit as "PriceTotal"
from Table3
I just want to store the value and then use it in the operation so I don't have to do the select again.
I'm not sure why it should be necessary to store the values in variables for usage in your case. I think the calculation can be done also by joining just the data (assuming that table3 contains a reference to table1 and table2).
Your example above would also not work, because TruckPrice and TruckUnits are no atomar results.
So please try to refactor your statement to use joins.

Maximo Conditional expression manager/Sql Query Builder

Can somebody help me in converting below mentioned query in to Maximo's where clause:
select distinct workorder.wonum from workorder inner join [assignment]
On workorder.wonum=[assignment].wonum
inner join amcrew
On amcrew.amcrew=[assignment].amcrew
inner join amcrewlabor
On amcrewlabor.amcrew=amcrew.amcrew
inner join labor
On amcrewlabor.laborcode=labor.laborcode
inner join person
on labor.laborcode=person.personid where amcrewlabor.laborcode='KELLYB'
KELLYB is PERSONID used here for just reference.
If you are using a custom search query in Maximo, you can try prepending your with in (your query)
For example, if you're in Maximo's work order tracking module, the application uses select * from workorder by default. Any time you add a search filter such as work order number (wonum), then the query appends to run a query as select * from workorder where wonum = '123' if 123 is the work order number you entered.
Your where clause might look something like this:
wonum in (
select distinct workorder.wonum
from workorder
join assignment on workorder.wonum=assignment.wonum
join amcrew on amcrew.amcrew=assignment.amcrew
join amcrewlabor on amcrewlabor.amcrew=amcrew.amcrew
join labor on amcrewlabor.laborcode=labor.laborcode
join person on labor.laborcode=person.personid
where amcrewlabor.laborcode='KELLYB'
)
The SQL that is generated in Microsoft Access will not necessarily work in Maximo without some modification.

Cannot link MS Access query with subquery

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.

Subsonic 3 Simple Query inner join sql syntax

I want to perform a simple join on two tables (BusinessUnit and UserBusinessUnit), so I can get a list of all BusinessUnits allocated to a given user.
The first attempt works, but there's no override of Select which allows me to restrict the columns returned (I get all columns from both tables):
var db = new KensDB();
SqlQuery query = db.Select
.From<BusinessUnit>()
.InnerJoin<UserBusinessUnit>( BusinessUnitTable.IdColumn, UserBusinessUnitTable.BusinessUnitIdColumn )
.Where( BusinessUnitTable.RecordStatusColumn ).IsEqualTo( 1 )
.And( UserBusinessUnitTable.UserIdColumn ).IsEqualTo( userId );
The second attept allows the column name restriction, but the generated sql contains pluralised table names (?)
SqlQuery query = new Select( new string[] { BusinessUnitTable.IdColumn, BusinessUnitTable.NameColumn } )
.From<BusinessUnit>()
.InnerJoin<UserBusinessUnit>( BusinessUnitTable.IdColumn, UserBusinessUnitTable.BusinessUnitIdColumn )
.Where( BusinessUnitTable.RecordStatusColumn ).IsEqualTo( 1 )
.And( UserBusinessUnitTable.UserIdColumn ).IsEqualTo( userId );
Produces...
SELECT [BusinessUnits].[Id], [BusinessUnits].[Name]
FROM [BusinessUnits]
INNER JOIN [UserBusinessUnits]
ON [BusinessUnits].[Id] = [UserBusinessUnits].[BusinessUnitId]
WHERE [BusinessUnits].[RecordStatus] = #0
AND [UserBusinessUnits].[UserId] = #1
So, two questions:
- How do I restrict the columns returned in method 1?
- Why does method 2 pluralise the column names in the generated SQL (and can I get round this?)
I'm using 3.0.0.3...
So far my experience with 3.0.0.3 suggests that this is not possible yet with the query tool, although it is with version 2.
I think the preferred method (so far) with version 3 is to use a linq query with something like:
var busUnits = from b in BusinessUnit.All()
join u in UserBusinessUnit.All() on b.Id equals u.BusinessUnitId
select b;
I ran into the pluralized table names myself, but it was because I'd only re-run one template after making schema changes.
Once I re-ran all the templates, the plural table names went away.
Try re-running all 4 templates and see if that solves it for you.

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