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Session : Querying : How to Query With Exact Match

By default Where method in Query uses case-insensitive match.

To perform case-sensitive match you should use exact parameter.

Syntax

IRavenQueryable<T> Where<T>(Expression<Func<T, int, bool>> predicate, bool exact);

IRavenQueryable<T> Where<T>(Expression<Func<T, bool>> predicate, bool exact);

Parameters
predicate Expression<Func<T, int, bool>> Predicate with match condition
exact bool Indicates if predicate should be matched in case-sensitive manner

Example I - Query With Exact Match

// load all entities from 'Employees' collection
// where FirstName equals 'Robert' (case sensitive match)
List<Employee> employees = session
    .Query<Employee>()
    .Where(x => x.FirstName == "Robert", exact: true)
    .ToList();
// load all entities from 'Employees' collection
// where FirstName equals 'Robert' (case sensitive match)
List<Employee> employees = await asyncSession
    .Query<Employee>()
    .Where(x => x.FirstName == "Robert", exact: true)
    .ToListAsync();
from Employees where exact(FirstName == 'Robert')

Example II - Query With Inner Exact Match

// return all entities from 'Orders' collection
// which contain at least one order line with
// 'Singaporean Hokkien Fried Mee' product
// perform a case-sensitive match
List<Order> orders = session
    .Query<Order>()
    .Where(x => x.Lines.Any(p => p.ProductName == "Singaporean Hokkien Fried Mee"), exact: true)
    .ToList();
// return all entities from 'Orders' collection
// which contain at least one order line with
// 'Singaporean Hokkien Fried Mee' product
// perform a case-sensitive match
List<Order> orders = await asyncSession
    .Query<Order>()
    .Where(x => x.Lines.Any(p => p.ProductName == "Singaporean Hokkien Fried Mee"), exact: true)
    .ToListAsync();
from Orders 
where exact(Lines[].ProductName == 'Singaporean Hokkien Fried Mee')