在vb.net中搜索程序的SQL查询

Question

Trying to figure out the right way to query a MySql database and find a user defined variable from a Textbox.Text property. I'm not sure what to put for the where clause in order to search every cell of every row for a match. I have looked at coalesce and contains, but neither are really making sense to me and I'm not sure if they are my best option. I'm thinking that the query string will look something like this:

SELECT * FROM table WHERE (I dont know) = '" & searchBarTextVariable & "'

Answer 1

Without a dynamic solution you will have to specify each column you'd like to search. This is a pretty fundamental part of working with a relational database; MySQL is no exception.

As mentioned in a @jadarnel27's comment, you should use parameters instead. Something like:

SELECT *
FROM table
WHERE someColumnA = @searchBarTextVariable
   OR someColumnB = @searchBarTextVariable
   OR someColumnC = @searchBarTextVariable
   OR someColumnD = @searchBarTextVariable

Answer 2

There is no specific syntax to search all columns, you have to list them out individually. You can write a query as follows.

SELECT * FROM table WHERE 
Field1 = '" & searchBarTextVariable & "'
OR Field2 = '" & searchBarTextVariable & "'
OR Field3 = '" & searchBarTextVariable & "'
OR Field4 = '" & searchBarTextVariable & "'
...

You should only list fields that are actually text, or be careful of conversion errors. Also watch out for SQL injection.