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C# SQLite Parameterized Select Using LIKE

I am trying to do an SQL query such as

SELECT * FROM [TABLE] WHERE hostname LIKE '%myhostname%';

This works fine in plain SQL, but when I use System.Data.SQLite in C#, it only works with a literal, not a parameter, such as

string sel = "SELECT * FROM [TABLE] WHERE hostname LIKE '%@host%'";
...
command.Parameters.AddWithValue("@host", "myhostname");

This returns no results.

like image 737
AdamC Avatar asked Dec 01 '10 22:12

AdamC


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2 Answers

You can't do that. The parameters must be complete values - it's not just a string substitution into the SQL. You could do this instead:

string sel = "SELECT * FROM [TABLE] WHERE hostname LIKE @host";
...
command.Parameters.AddWithValue("@host", "%myhostname%");
like image 65
Mark Byers Avatar answered Oct 04 '22 13:10

Mark Byers


Easiest way to do this is to use '||'

Use :

const string qry = "SELECT SiteNum FROM WorkTable WHERE WTName LIKE @wtName || '%' ";

Instead Of:

const string qry = "SELECT SiteNum FROM WorkTable WHERE WTName LIKE @wtName%";

I have already answered here

like image 41
Kas Avatar answered Oct 04 '22 13:10

Kas