Code for hybird search

Question

1.00/5 (1 vote)

See more:

System.Data.SqlClient.SqlException: 'Incorrect syntax near '='.'

What I have tried:

C#

if (textBox1.Text != "")
            {
                Query += "and Serial_Number='" + textBox1.Text + "'";
            }

            if (bPersianCalenderTextBox2.Text != "")
            {
                Query += "and Received_Date = '" + bPersianCalenderTextBox2.Text + "'";
            }

            if (bPersianCalenderTextBox1.Text != "")
            {
                Query += "and Entry_Date = '" + bPersianCalenderTextBox1.Text + "'";
            }

            DataSet ds = new DataSet();
            SqlDataAdapter adp = new SqlDataAdapter();
            adp.SelectCommand = new SqlCommand();
            adp.SelectCommand.Connection = con;
            adp.SelectCommand.CommandText = "select * from tblSaleServices where 1=1 and Entry_Date != '' and Repair_Date != '' and Received_Date !=''" + Query;
            adp.Fill(ds, "tblSaleServices");
            dataGridView1.DataSource = ds;
            dataGridView1.DataMember = "tblSaleServices";

Posted 3-Aug-22 7:36am

SaeedZer0

Updated 3-Aug-22 9:15am

PIEBALDconsult

v2

Add a Solution

Comments

PIEBALDconsult 3-Aug-22 14:54pm

!=''" + Query;

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Answer 1 · 2022-08-03T08:33:00

Don't do it like that! Never concatenate strings to build a SQL command. It leaves you wide open to accidental or deliberate SQL Injection attack which can destroy your entire database. Always use Parameterized queries instead.

When you concatenate strings, you cause problems because SQL receives commands like:

SQL

SELECT * FROM MyTable WHERE StreetAddress = 'Baker's Wood'

The quote the user added terminates the string as far as SQL is concerned and you get problems. But it could be worse. If I come along and type this instead: "x';DROP TABLE MyTable;--" Then SQL receives a very different command:

SQL

SELECT * FROM MyTable WHERE StreetAddress = 'x';DROP TABLE MyTable;--'

Which SQL sees as three separate commands:

SQL

SELECT * FROM MyTable WHERE StreetAddress = 'x';

A perfectly valid SELECT

SQL

DROP TABLE MyTable;

A perfectly valid "delete the table" command

SQL

--'

And everything else is a comment.
So it does: selects any matching rows, deletes the table from the DB, and ignores anything else.

So ALWAYS use parameterized queries! Or be prepared to restore your DB from backup frequently. You do take backups regularly, don't you?

Fix that throughout your whole app and you will almost certainly find that your problem has disappeared at the same time.

Patrice T · Answer 2 · 2022-08-03T09:15:00

Quote:
System.Data.SqlClient.SqlException: 'Incorrect syntax near '='.'

The problem is that nobody here can know what is the real SQL query, because it depend on user input.

C#

adp.SelectCommand.Connection = con;
// Here, print the 'CommandText' that you build in next line
adp.SelectCommand.CommandText = "select * from tblSaleServices where 1=1 and Entry_Date != '' and Repair_Date != '' and Received_Date !=''" + Query;

Then you will know what is the exact query you have. (Add this print to the question.

Never build an SQL query by concatenating strings. Sooner or later, you will do it with user inputs, and this opens door to a vulnerability named "SQL injection", it is dangerous for your database and error prone.
A single quote in a name and your program crash. If a user input a name like "Brian O'Conner" can crash your app, it is an SQL injection vulnerability, and the crash is the least of the problems, a malicious user input and it is promoted to SQL commands with all credentials.
SQL injection - Wikipedia[^]
SQL Injection[^]
SQL Injection Attacks by Example[^]
PHP: SQL Injection - Manual[^]
How can I explain SQL injection without technical jargon? - Information Security Stack Exchange[^]

Code for hybird search

2 solutions

Solution 1

Solution 2

Add your solution here

Preview 0