When using the SqlBuilder class of DBExtensions, is it possible to build multiple select statements that are executed in a single round trip?
Something along the lines of:
select t1.* from Table1 t1 where t1.Foo = 'Bar 1';
select t2.* from Table2 t2 where t2.Foo = 'Bar 2';
For the building part, you can do:
var query1 = SQL
.SELECT("t1.*")
.FROM("Table1 t1")
.WHERE("t1.Foo = {0}", "Bar 1");
var query2 = SQL
.SELECT("t2.*")
.FROM("Table2 t2")
.WHERE("t2.Foo = {0}", "Bar 2");
var batchQuery = SqlBuilder.JoinSql(";", query1, query2);
About execution, I have no idea if your ADO.NET provider supports batch SELECT queries, maybe you want to do a UNION query instead?
Related
I want to rewrite the following query using jooq:
with first_temp as (
select a.id as lie_id
from first_table a
where a.some_Field = 100160
), second_temp as (
select b.id as ben_id
from second_table b
where b.email = 'some.email#gmail.com'
) insert into third_table (first_table_id, second_table_id)
select a.lie_id, b.ben_id from first_temp a, second_temp b;
I was trying something like the following:
DriverManager.getConnection(url, login, password).use {
val create = DSL.using(it, SQLDialect.POSTGRES)
create.with("first_temp").`as`(create.select(FIRST_TABLE.ID.`as`("lie_id")))
.with("second_temp").`as`(create.select(SECOND_TABLE.ID.`as`("ben_id")))
.insertInto(THIRD_TABLE, THIRD_TABLE.FIRST_TABLE_ID, THIRD_TABLE.SECOND_TABLE_ID)
.select(create.select().from("first_temp", "second_temp"), create.select().from("second_temp")))
}
But without success.
Your fixed query
// You forgot FROM and WHERE clauses in your CTEs!
create.with("first_temp").`as`(
create.select(FIRST_TABLE.ID.`as`("lie_id"))
.from(FIRST_TABLE)
.where(FIRST_TABLE.SOME_FIELD.eq(100160)))
.with("second_temp").`as`(
create.select(SECOND_TABLE.ID.`as`("ben_id"))
.from(SECOND_TABLE)
.where(SECOND_TABLE.EMAIL.eq("some.email#gmail.com")))
.insertInto(THIRD_TABLE, THIRD_TABLE.FIRST_TABLE_ID, THIRD_TABLE.SECOND_TABLE_ID)
// You had too many queries in this part of the statement, and
// didn't project the two columns you were interested int
.select(create.select(
field(name("first_temp", "lie_id")),
field(name("second_temp", "ben_id")))
.from("first_temp", "second_temp"))
// Don't forget this ;-)
.execute();
But frankly, why even use CTE at all? Your query would be much simpler like this, both in SQL and in jOOQ (assuming that you really want this cartesian product):
Better SQL Version
insert into third_table (first_table_id, second_table_id)
select a.id, b.id
from first_table a, second_table b
where a.some_field = 100160
and b.email = 'some.email#gmail.com';
Better jOOQ Version
create.insertInto(THIRD_TABLE, THIRD_TABLE.FIRST_TABLE_ID, THIRD_TABLE.SECOND_TABLE_ID)
.select(create.select(FIRST_TABLE.ID, SECOND_TABLE.ID)
.from(FIRST_TABLE, SECOND_TABLE)
.where(FIRST_TABLE.SOME_FIELD.eq(100160))
.and(SECOND_TABLE.EMAIL.eq("some_email#gmail.com")))
.execute();
Is it possible to do orderby expression using linq query expression based on dynamic string parameter? because the query i have is producing weird SQL query
my linq:
var product = from prod in _context.Products
join cat in _context.Categories on prod.CategoryId equals cat.CategoryId
join sup in _context.Suppliers on prod.SupplierId equals sup.SupplierId
orderby sortParam
select new ProductViewModel
{
ProductName = prod.ProductName,
ProductId = prod.ProductId,
QuantityPerUnit = prod.QuantityPerUnit,
ReorderLevel = prod.ReorderLevel,
UnitsOnOrder = prod.UnitsOnOrder,
UnitPrice = prod.UnitPrice,
UnitsInStock = prod.UnitsInStock,
Discontinued = prod.Discontinued,
Category = cat.CategoryName,
Supplier = sup.CompanyName,
CategoryId = cat.CategoryId,
SupplierId = sup.SupplierId
};
where var sortParam = "prod.ProductName"
The code above produces weird sql where order by sortParam is being converted to (SELECT 1). Full query catched by sql profiler below:
exec sp_executesql N'SELECT [prod].[ProductName], [prod].[ProductID], [prod].[QuantityPerUnit], [prod].[ReorderLevel], [prod].[UnitsOnOrder], [prod].[UnitPrice], [prod].[UnitsInStock], [prod].[Discontinued], [cat].[CategoryName] AS [Category], [sup].[CompanyName] AS [Supplier], [cat].[CategoryID], [sup].[SupplierID]
FROM [Products] AS [prod]
INNER JOIN [Categories] AS [cat] ON [prod].[CategoryID] = [cat].[CategoryID]
INNER JOIN [Suppliers] AS [sup] ON [prod].[SupplierID] = [sup].[SupplierID]
ORDER BY (SELECT 1)
OFFSET #__p_1 ROWS FETCH NEXT #__p_2 ROWS ONLY',N'#__p_1 int,#__p_2 int',#__p_1=0,#__p_2=10
I'm seeing a lot of people doing linq order by using dynamic parameter but all of them use lambda not query expression, please enlighten me
As was already mentioned, you are passing a string value instead of an expression that reflects the column name. There are options for what you want however, see for example here.
I need to implement the following T-SQL clause ....
SELECT
CONCAT( RANK() OVER (ORDER BY [Order].codOrder, [PackedOrder].codPackedProduct ), '/2') as Item,
[Order].codOrder as [OF],
[PackedOrder].codLine as [Ligne],
[PackedOrder].codPackedProduct as [Material], ----------------------
[Product].lblPProduct as [Product],
[PackedProduct].lblPackedProduct as [MaterialDescription],
[PackedOrder].codPackedBatch as [Lot],
[Product].codCustomerColor as [ReferenceClient],
[PackedOrder].nbrPackedQuantity as [Quantity],
[PackedOrder].nbrLabelToPrint as [DejaImprime]
FROM [Order] INNER JOIN PackedOrder
ON [Order].codOrder = PackedOrder.codOrder INNER JOIN Product
ON [Order].codProduct = Product.codProduct INNER JOIN PackedProduct
ON PackedOrder.codPackedProduct = PackedProduct.codPackedProduct
Where [Order].codOrder = 708243075
So Far, I'm able to do:
var result =
from order1 in Orders
join packedorder1 in PackedOrders on order1.codOrder equals packedorder1.codOrder
join product1 in Products on order1.codProduct equals product1.codProduct
join packedproduct1 in PackedProducts on packedorder1.codPackedProduct equals packedproduct1.codPackedProduct
where order1.codOrder == _order.codOrder
select new FinishedProductPrintingM
{
OF = order1.codOrder,
Ligne = packedorder1.codLine,
Material = packedorder1.codPackedProduct,
Produit = product1.codProductType,
MaterialDescription = packedproduct1.lblPackedProduct,
Lot = packedorder1.codPackedBatch,
RéférenceClient = product1.codCustomerColor,
Quantité = packedorder1.nbrPackedQuantity,
Déjàimprimé = packedorder1.nbrLabelPrinted
};
Please let me know if its possible or not. I need to display the Items in such a way.Please feel free to add your valuable comments.
I am not aware how to use concat and Rank over function in LINQ.
Can anyone help me to convert my SQL query into LINQ?
I have the following criteria query, which retrieves some fields from Anfrage and Sparte entities and also the translated string for the sparte.i18nKey.
This works as expected if I dont use orderBy.
Now I have the requirement to sort by the translated string for sparte.i18nKey and using the orderBy as shown below, results in QuerySyntaxException: unexpected AST node
So the problem must be the subselect in the orderBy clause!
select distinct new
my.domain.model.dto.AnfrageDTO(
anfrage0.id,
anfrage0.name,
anfrage0.sparte.id,
anfrage0.sparte.i18nKey,
-- retrieve translated string for sparte.i18nKey
(select rb0.value from at.luxbau.mis2.domain.model.ResourceBundleEntity as rb0
where (anfrage0.sparte.i18nKey = rb0.key) and (rb0.language = 'de'))
)
from my.domain.model.impl.Anfrage as anfrage0
left join anfrage0.sparte as sparte
order by (
-- sort by translated string for sparte.i18nKey
select rb1.value
from my.domain.model.ResourceBundleEntity as rb1
where (anfrage0.sparte.i18nKey = rb1.key) and (rb1.language = 'de')
) asc
My Java code looks like this:
private List<AnfrageDTO> getAnfragen() {
CriteriaBuilder cb = entityManager.getCriteriaBuilder();
CriteriaQuery<AnfrageDTO> query = cb.createQuery(AnfrageDTO.class);
Root<Anfrage> anfrage = query.from(Anfrage.class);
anfrage.join(Anfrage_.sparte, JoinType.LEFT);
query.select(cb.construct(AnfrageDTO.class,
anfrage.get(Anfrage_.id),
anfrage.get(Anfrage_.name),
anfrage.get(Anfrage_.sparte).get(Sparte_.id),
anfrage.get(Anfrage_.sparte).get(Sparte_.i18nKey),
// create subquery for translated sparte.i18nKey
createResourceBundleSubQuery(cb, query, anfrage.get(Anfrage_.sparte).get(Sparte_.i18nKey)).getSelection()));
TypedQuery<AnfrageDTO> tq = entityManager
.createQuery(query)
// use subquery to sort by translated sparte.i18nKey
.orderBy(cb.asc(createResourceBundleSubQuery(cb, query, anfrage.get(Anfrage_.sparte).get(Sparte_.i18nKey))));
tq.setMaxResults(10);
List<AnfrageDTO> anfragen = tq.getResultList();
return anfragen;
}
public Subquery<String> createResourceBundleSubQuery(CriteriaBuilder cb, CriteriaQuery<?> query, <String> expr) {
Subquery<String> subquery = query.subquery(String.class);
Root<ResourceBundleEntity> rb = subquery.from(ResourceBundleEntity.class);
subquery
.select(rb.get(ResourceBundleEntity_.value))
.where(cb.and(
cb.equal(expr, rb.get(ResourceBundleEntity_.key)),
cb.equal(rb.get(ResourceBundleEntity_.language), "de")));
return subquery;
}
Using a native SQL query with subselect in orderBy works also as expected.
select distinct
anfrage0_.id,
anfrage0_.name,
anfrage0_.sparte_id,
sparte4_.i18n_key,
(select rb3.i18n_value from resource_bundle rb3 where rb3.language_code = 'de' and rb3.i18n_key = sparte4_.i18n_key) as sparte_i18n_value
from
mis2.anfrage anfrage0_
left outer join mis2.sparte sparte4_ on anfrage0_.sparte_id = sparte4_.id
order by (
select rb.i18n_value
from mis2.resource_bundle rb
where sparte4_.i18n_key = rb.i18n_key and rb.language_code = 'de'
) asc
Also using an alias in the native SQL query works also as expected.
select distinct
anfrage0_.id,
anfrage0_.name,
anfrage0_.sparte_id,
sparte4_.i18n_key,
(select rb3.i18n_value from resource_bundle rb3 where rb3.language_code = 'de' and rb3.i18n_key = sparte4_.i18n_key) as sparte_i18n_value
from
mis2.anfrage anfrage0_
left outer join mis2.sparte sparte4_ on anfrage0_.sparte_id = sparte4_.id
order by sparte_i18n_value
asc
It would be great if JPA Criteria API would support using an alias in orderBy clause!
Any hints welcome - Thank you!
My environment is WildFly 11 and PostgreSQL 9.6.
JPA doesn't support passing parameter in order by clause, your problem has been asked before: Hibernate Named Query Order By parameter
I have a linq query that works fine when I join two tables, but when I include another table, it does not return data. Please help me figure out what I am doing wrong.
First Linq returns data:
var q = (from c in _context.Complaint
join cl in _context.Checklist on c.COMP_ID equals cl.COMP_ID into clleft
from cls in clleft.DefaultIfEmpty()
orderby c.timestamp descending
select new
{
FileNum = c.FileNum
}).AsQueryable().Distinct();
return q;
When I add this table, no data returns
var q = (from c in _context.Complaint
join cl in _context.Checklist on c.COMP_ID equals cl.COMP_ID into clleft
from cls in clleft.DefaultIfEmpty()
join oim in _context.OIM_EMPLOYEE on cls.MonitorEnteredEmpID equals oim.EmpID into oimleft
from oims in oimleft.DefaultIfEmpty()
orderby c.timestamp descending
select new
{FileNum = c.FileNum
}).AsQueryable().Distinct();
return q;