How can I execute a multi Join SQL query in c#

Question

Using IDataReader in c# to pull a list of host names from a database that correspond to a specific business unit, but can't figure out what is wrong. I am guessing that there are too many arguments in the SQL statement, or perhaps the ExecuteReader method here should not be used. I cannot create a SP in the target DB so I am left with running the query in some other manner. Any help will be greatly appreciated.

    public static IDataReader GetCETHostsList()
    {
        string mySQL = @"SELECT distinct(dbo.Infrastructure.Hostname) dbo.Application_Infrastructure 
                        INNER JOIN dbo.Applications ON dbo.Application_Infrastructure.ID = dbo.Applications.ID
                        INNER JOIN dbo.Infrastructure ON dbo.Application_Infrastructure.InfrastructureID = dbo.Infrastructure.InfrastructureId 
                        WHERE Unit is not null
                        AND dbo.Applications.Unit like '%Terminal%' 
                        AND (dbo.Infrastructure.Hostname like '%ST%' or dbo.Infrastructure.Hostname like '%TR%' )";
        return DatabaseFactory.CreateDatabase("myDB").ExecuteReader(mySQL);
    }

What sort of error do you see when you try to run this command? — Adil B, Apr 22 '14 at 22:16
There's no reason this shouldn't work, except for some error in your sql, or a noddy reason like being connected to the wrong db or some such. — Tony Hopkinson, Apr 22 '14 at 22:18
Are you using mySQL or just named the variable mySQL? If it is mySQL you must close the query with a semicolon. — Cyassin, Apr 22 '14 at 22:19
I'm not familiar with MySQL specifically, but it looks to me like you are missing a `FROM sometable` before the first `INNER JOIN`. — 500 - Internal Server Error, Apr 22 '14 at 22:19
You "can't figure out what is wrong"? Generally neither can we without some clue as to the error message. — Nick.Mc, Apr 22 '14 at 22:28

score 1 · Answer 1 · answered Apr 22 '14 at 22:19

1

You're missing the FROM keyword.

Generally, if you use SQL embedded in C# programs, it's really a lot easier if you run the SQL in Query Analyzer / SQL Management Studio or something first. MS SQL Express is free; or VS Pro can run sql queries too.

answered Apr 22 '14 at 22:19

Chris F Carroll

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How can I execute a multi Join SQL query in c#

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