How do I use the SQL WHERE IN construct with PetaPoco?
I have a database table named Tags (Id, Name) from which I would like to select the ones where the name matches a name in a list. In SQL I would use something like:
Select * from Tags Where Name In ('Name1', 'Name2', 'xxx...)
But now using PetaPoco in an ASP.Net MVC3 project I'm stuck figuring out how to do it properly. So far I've tried:
var tagsToFind = new string[] { "SqlServer", "IIS" };
var sql = PetaPoco.Sql.Builder.Select("*").From("Tags").Where("Name in (@0)", tagsToFind);
var result = db.Query<Tag>(sql);
Which results in the following SQL, where only the first name in my list of tagsToFind is used to match the table data as opposed to all of them.
SELECT * FROM Tags WHERE (Name in (@0)) -> @0 [String] = "SqlServer"
It's a little frustrating, knowing this probably isn't so hard.. any help is appreciated!
Update: I found out that it can be done in another way
开发者_运维百科var sql = PetaPoco.Sql.Builder.Append("Select * from tags Where Name IN (@0", tagNames[0]);
foreach (string tagName in tagNames.Where(x => x != tagNames[0])) {
sql.Append(", @0", tagName);
}
sql.Append(")");
var result = db.Query<Tag>(sql)
which gets me what I want while using sqlparameters. So I guess it's good enough for now, although not super pretty.
/Mike
This will work except you can't use the @0 (ordinal) syntax. You must use named parameters, otherwise it thinks they are individual parameters.
var tagsToFind = new string[] { "SqlServer", "IIS" };
var sql = PetaPoco.Sql.Builder.Select("*").From("Tags").Where("Name in (@tags)", new { tags = tagsToFind });
var result = db.Query<Tag>(sql);
This will result in
select * from Tags where name in (@0, @1);
@0 = SqlServer, @1 = IIS
Posting this for future seekers. This works.
public IEnumerable<Invoice> GetInvoicesByStatus(List<string> statuses)
{
return _database.Fetch<Invoice>(@"
select *
from Invoices
where Status IN (@statuses)",
new { statuses });
}
If you want to use array class with Petapoco you can use this
string[] array = new string[] {"Name1","Name2" };
var foo = BasicRepository<Personnel>.Fetch("WHERE PersonnelId IN (@0)", array.ToArray());
Here is an another sample:
program.cs:
public static void Main(string[] args)
{
using (var db = new PetaPoco.Database("Northwind"))
{
var sql = "Select * from customers where Country in (@Countries)";
var countries = new { @Countries = new string[] { "USA", "Mexico" } };
var customers = db.Query<Customer>(sql, countries);
foreach (var customer in customers)
{
Console.WriteLine("{0} - {1} from {2}", customer.CustomerID, customer.CompanyName, customer.Country);
}
}
}
customer.cs:
public class Customer
{
public string CustomerID { get; set; }
public string Address { get; set; }
public string City { get; set; }
public string CompanyName { get; set; }
public string ContactName { get; set; }
public string ContactTitle { get; set; }
public string Country { get; set; }
public string Fax { get; set; }
public string Phone { get; set; }
public string PostalCode { get; set; }
public string Region { get; set; }
}
App.config: (Connectionstring uses localdb connectionstring, so you might change it.)
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
</startup>
<connectionStrings>
<clear/>
<add name="Northwind"
connectionString="Data Source=(localdb)\v11.0;Initial Catalog=northwind;Integrated Security=True;"
providerName="System.Data.SqlClient"/>
</connectionStrings>
</configuration>
Maybe, it's not a good way setting too many params in sql, the max params limit is 2100.
@Murat
string[] array = new string[] {"Name1","Name2" };
var foo = BasicRepository<Personnel>.Fetch("WHERE PersonnelId IN > (@0)", array.ToArray());
Constructing stander SQL in string, and check the LAST excute-sql, alway match your need.
var userIDs = from user in UserList select user.UserID;
db.Delete<User>("where UserID in (" + string.Join(",", userIDs) + ")");
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