Interface IQueryBase<T>

Interface, which describe class for executing query.

Instance which implement this interface can be used for creating and executing query for T model.

Namespace: Kros.KORM.Query

Assembly: Kros.KORM.dll

Syntax

public interface IQueryBase<T> : IOrderedQueryable<T>, IQueryable<T>, IEnumerable<T>, IOrderedQueryable, IQueryable, IEnumerable

Type Parameters

Name	Description
T	Type of model class.

Methods

AsDbSet()

Returns the collection of all entities that can be queried from the database.

Declaration

IDbSet<T> AsDbSet()

Returns

Type	Description
IDbSet<T>	DbSet<T>.

ExecuteScalar()

Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

Declaration

object ExecuteScalar()

Returns

Type	Description
System.Object	The first column of the first row in the result set, or null if the result set is empty. Returns a maximum of 2033 characters.

Examples

                var id = (int)database.Query<Person>()
                .Select(p => new { p.Id })
                .Where("FirstName = @p1 AND LastName = @p2", "Michael", "Štúr")
                .ExecuteScalar();

ExecuteScalar<TRet>()

Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

Declaration

TRet? ExecuteScalar<TRet>()

    where TRet : struct

Returns

Type	Description
System.Nullable<TRet>	The first column of the first row in the result set as nullable type of TRet. If the result set is empty, then HasValue is false. Returns a maximum of 2033 characters.

Type Parameters

Name	Description
TRet	Return type.

Examples

                var id = (int)database.Query<Person>()
                .Select(p => new { p.Id })
                .Where("FirstName = @p1 AND LastName = @p2", "Michael", "Štúr")
                .ExecuteScalar();

ExecuteStringScalar()

Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

Declaration

string ExecuteStringScalar()

Returns

Type	Description
System.String	The first column of the first row in the result set as string, or null if the result set is empty. Returns a maximum of 2033 characters.

Examples

                var id = (int)database.Query<Person>()
                .Select(p => new { p.Id })
                .Where("FirstName = @p1 AND LastName = @p2", "Michael", "Štúr")
                .ExecuteScalar();