Does Dapper use numbered parameters such as in Massive

dapper massive sql-server

Question

Does Dapper use numbered parameters such as in Massive(@0, @1, ...) unlike named (@a, @b, ...)?

It is necessary to create a query as

//select @0 as val union select @1 union select @2 union select @3 union select @4 
//union select @5 union select @6 union select @7 union select @8 union select @9
var sb = new StringBuilder("select @0 as val");
for (int i = 1; i < 10; i++)
{
    sb.AppendFormat(" union select @{0}", i);
}
var query = sb.ToString();
//---Dapper = fail
var db = Connection;
var list = db.Query(query, param: new object[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 });
//---Massive = ok
var db2 = new Massive.DynamicModel(coins);
var list2 = db2.Query(query, args: new object[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 });

What are the solutions to the problem for Dapper?

Accepted Answer

Massive uses positional arguments in their queries but dapper uses named ones. So in massive you can pass in parameter arrays like: new int[] {1,2,3} while in dapper you need to pass in parameter objects like new { a = 1, b = 2 }.

To achieve a similar solution with dapper you can create a DynamicParameters object where you can pass your parameters dictionary where the key is the name of the parameter and value is the value of parameter, something like {"0",0}, {"1", 1}, etc

You can easily turn an array to a dictionary with LINQ:

var dictionary = new object[] {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
    .Select((item, ind) => new {ind = ind.ToString(), item})
    .ToDictionary(item => item.ind, item => item.item);

DynamicParameters p = new DynamicParameters(dictionary);

var list = db.Query(query, param: p);



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