SQL SELECT statement with text field C# .NET

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I have an SQL database, it contains a table named (users), the name field is defined as text.
In the C# code I want to search the database for a specific name like this:

C#

SQLCommand c = new SQLCommand(connection);
c.CommandType = CommandType.Text;
c.CommandText = "SELECT * FROM users WHERE name=\'" + textbox1.text + "\'";
adapter.Fill(dataset1,"users");

When I execute it returns this error:

The data types text and varchar are incompatible in the equal to operator.

Any ideas?

Posted 26-Nov-13 7:34am

Hussain Marzah

Updated 26-Nov-13 7:36am

RaisKazi

v2

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Herman<T>.Instance 26-Nov-13 13:47pm

Why have you choosen for TEXT as columntype in stead of NVARCHAR?

2 solutions

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Jawad Ahmed Tanoli · Accepted Answer · 2013-11-26T07:53:00

Solution 2

c.CommandText = "SELECT * FROM users WHERE name Like '" + textbox1.text + "'";
or
c.CommandText = "SELECT * FROM users WHERE CONVERT(VARCHAR, name) ='" + textbox1.text + "'";

text is deprecated Changing to varchar(max) will be easier to work.

Posted 26-Nov-13 7:53am

Jawad Ahmed Tanoli

Maciej Los · Accepted Answer · 2013-11-26T07:50:00

Solution 1

I would suggest you to use Stored procedure instead command text in a code behind.

Please, see: Return Data from a Stored Procedure[^]
How to: Execute a Stored Procedure that Returns Rows[^]

SP should looks like this one:

SQL

SELECT *
FROM [users]
WHERE [name]=@username

By The Way: Do not use reserved words[^] as a name of fields, etc.

Posted 26-Nov-13 7:50am

Maciej Los

Updated 26-Nov-13 7:51am

v2

Comments

RaisKazi 26-Nov-13 15:46pm

My 5!

Maciej Los 26-Nov-13 15:47pm

Thank you ;)