I have a Geography column in a table in SQL Server and would like to filter rows with a specific geometry type, e.g. all records where geometry type is 'Point'
The SQL query would look like
select * from GeometryTable g where g.Geography.STGeometryType() = 'Point'
How can I create a criteria for that? The criteria is going to be used with other criterias
criteria.Add(Restrictions.Add(<Geography.STGeometryType()>, some.Value)
Thanks
Use this syntax:
var criteria = session.CreateCriteria<Geometry>();
criteria.Add
(
Expression.Sql(" {alias}.[Geography].STGeometryType() = ? "
, "Point" // a place for your parameter
, NHibernate.NHibernateUtil.String)
);
var list = criteria.List<Geometry>();
Related
How to Convert this sql query to Linq.
select sum(OutstandingAmt)from IvfReceiptDetails where IvfReceiptId IN(select IvfReceiptId from IvfReceipts where PatientId = 'SI-49650')
I think it is easier to translate SQL using query comprehension syntax instead of lambda syntax.
General rules:
Translate inner queries into separate query variables
Translate SQL phrases in LINQ phrase order
Use table aliases as range variables, or if none, create range variables from table names
Translate IN to Contains
Translate SQL functions such as DISTINCT or SUM into function calls on the entire query.
Here is the code:
var IvfReceiptIds = from IvfReceipt in IvfReceipts
where IvfReceipt.PatientId = "SI-49650"
select IvfReceipt.IvfReceiptId;
var OutstandingAmtSum = (from IvfReceiptDetail in IvfReceiptDetails
where IvfReciptIds.Contains(IvfReceiptDetail.IvfReceiptId)
select IvfReceiptDetail.OutstandingAmt).Sum();
Try this, First get all IvfReceiptId in array based on your inner query used in where condition then check contains. Change name of your _context if it's different.
var arrIvfReceiptId = _context.IvfReceiptDetails.Where(p=>p.PatientId == "SI-49650").ToArray();
var sum = (from ird in _context.IvfReceiptDetails.Where(p=> arrIvfReceiptId.Contains(p.IvfReceiptId))
select OutstandingAmt).Sum();
Good Day,
I am querying my database using Linq and I have run into a problem, the query searched a column for a search phrase and based on if the column has the phrase, it then returns the results, The query is below,
Dim pdb = New ProductDataContext()
Dim query =
From a In pdb.tblUSSeries
Join b In pdb.tblSizes_ On a.Series Equals b.Series
Where
a.Series.ToString().Equals(searchString) Or
b.Description.Contains(searchString) Or Not b.Description.Contains(Nothing)
Order By b.Series, b.OrderCode Ascending
Select New CustomSearch With
{
.Series = a.Series,
.SeriesDescription= a.Description,
.Coolant = a.Coolant,
.Material = a.Material,
.Standard = a.Standard,
.Surface = a.Surface,
.Type = a.Type,
.PointAngle = a.PointAngle,
.DiaRange = a.DiaRange,
.Shank = b.Shank,
.Flutes = b.Flutes,
.EDPNum = b.EDPNum,
.SizesDescription = b.Description,
.OrderCode = b.OrderCode
}
Return query
I think the problem is that, in the table certain rows are NULL, so when it is checking the column for the phrase and it encounters a row that is null it, breaks and returns this error,
The cast to value type 'System.Int32' failed because the materialized value is null. Either the result type's generic parameter or the query must use a nullable type.
I have ran this query against another column that has all the rows populated with data and it returns the results ok.
So my question is how can I write it in VB to query the db with the supplied searchstring and return the results, when some of the rows in the columns have null values.
Any help would be great.
The exception occurs when you make the projection (i.e. select new CustomSearch)
And yes your trying to assign Null to some int property
(Not sure which one of your properties that is)
one of 2 choices :
1) Use nullalbe types for your properties (or just that one property).
2) project with an inline If ( ?? in C#) , I don't know VB so don't catch me on the syntax.
Taking Series just as an example i don't know if it's an int or if that's the problematic property
Select New CustomSearch With
{
.Series = If(a.Series Is Nothing,0, CInt(a.Series))
}
In C#
Select new CustomSearch
{
Series = a.Series ?? 0;
}
Let's say I have a Persons table with two columns:
ID (Uniqueidentifier)
Name (NChar)
I need to get all my persons first:
Dim data = (From p In Persons Select p).ToList
Now that I got all persons in the data variable, is it possible to query this result using a string query? Like...
Dim filtered = (From p In data Select p).Where("Name Like '%John%').ToList
?
I need to build the query on the fly.
Thanks
var filtered = data.Where(a =>
SqlMethods.Like(a.name.ToString(), "%" +
Request.QueryString["search"] + "%"));
i use querystring as an example for dynamic value, and use it in sql like method,
which is similiar to sql like, in your case "request.querystring["search"] value is john"
Try this:
from p in data
where SqlMethods.Like(p.Name, "%"+parameter+"%")
select p;
parameter in your example should be John.
I have a wrapped fluent nhibernate framework that I'm reusing and have no control over the actual mapping.
In my entity object I have a property mapped as string to an XML column in sql.
Hence when I run a query like:
var myResult = (from myTable in DataManager.Session.Query<Table>()
where myTable.thatXmlFieldWhichIsMappedAsString.Contains(AnXmlSnippet))
select myTable).FirstOrDefault();
It is trying to use the LIKE operator in SQL which is invalid on that column type.
How can I get around this without having to select all the rows and converting to List first?
In case, that we do not need .Query() (LINQ), and we can use Criteria query or QueryOver, we can use conversion:
// the projection of the column with xml
// casted to nvarchar
var projection = Projections
.Cast(NHibernateUtil.StringClob
, Projections.Property("thatXmlFieldWhichIsMappedAsString"));
// criteria filtering with LIKE
var criteria = Restrictions.Like(projection, "searched xml");
// query and result
var query = session.QueryOver<MyEntity>()
.Where(criteria)
;
var result = query
.SingleOrDefault<MyEntity>()
;
From my experience this could lead to conversion into small nvarchar(255) - sql server... Then we can do it like this:
var projection = Projections
.SqlProjection("CAST(thatXmlFieldWhichIsMappedAsString as nvarchar(max)) AS str"
, new string[]{}
, new NHibernate.Type.IType[]{}
);
I was trying to figure out how can I set multiple parameters for the IN clause in my SQL query using PreparedStatement.
For example in this SQL statement, I'll be having indefinite number of ?.
select * from ifs_db where img_hub = ? and country IN (multiple ?)
I've read about this in
PreparedStatement IN clause alternatives?
However I can't figure it out how to apply it to my SQL statement above.
There's not a standard way to handle this.
In SQL Server, you can use a table-valued parameter in a stored procedure and pass the countries in a table and use it in a join.
I've also seen cases where a comma-separated list is passed in and then parsed into a table by a function and then used in a join.
If your countries are standard ISO codes in a delimited list like '#US#UK#DE#NL#', you can use a rather simplistic construct like:
select * from ifs_db where img_hub = ? and ? LIKE '%#' + country + '#%'
Sormula will work for any data type (even custom types). This example uses int's for simplicity.
ArrayList<Integer> partNumbers = new ArrayList<Integer>();
partNumbers.add(999);
partNumbers.add(777);
partNumbers.add(1234);
// set up
Database database = new Database(getConnection());
Table<Inventory> inventoryTable = database.getTable(Inventory.class);
ArrayListSelectOperation<Inventory> operation =
new ArrayListSelectOperation<Inventory>(inventoryTable, "partNumberIn");
// show results
for (Inventory inventory: operation.selectAll(partNumbers))
System.out.println(inventory.getPartNumber());
You could use setArray method as mentioned in the javadoc below:
http://docs.oracle.com/javase/6/docs/api/java/sql/PreparedStatement.html#setArray(int, java.sql.Array)
Code:
PreparedStatement statement = connection.prepareStatement("Select * from test where field in (?)");
Array array = statement.getConnection().createArrayOf("VARCHAR", new Object[]{"AA1", "BB2","CC3"});
statement.setArray(1, array);
ResultSet rs = statement.executeQuery();