How do I check if data is in a database? (Visual basic 2010) (SQL)?

Question

I need to check if a certain 'seat number' has already been entered into the database so i can avoid double booking. But I don't know how to check if that data is in the data base..
For example
if data is not in data base
book seat
else
do not book
end if

Answer 1

Using SQL

check if database exists

check if table exists

use SELECT COUNT(*) to see if records exist

Answer 2

I don't know how big your data base is but you could write a SQL statement that will pull the information for you.



select

bookseat, (another primary field)

From

Seats (you data base name)



where

Data field ='2/23/2013' (if you have a data in there you can make your list smaller)





If you only know the name of the table then you can just do



select*

From

tablename



but this will pull everything.

Answer 3

Why do you utilize a photo field and not a label? i've got self assurance with Label is fairly straightforward you are able to make a label on the comparable place, length, heritage and foreground shade of the textbox password initiate with practice label and cover textbox. while person click on label, in the label click experience you cover label and practice textbox Sub label_click ... Label1.seen=fake Textbox1.seen=genuine end sub Use textbox password char to set character to coach once you digit password while person press return you cover textbox, reproduction password with label1.text fabric = textbox1.text fabric and practice label