Compile all values across multiple delimited strings into a table - sql

Question

I am collecting responses to an online survey form in a table like this:
CREATE TABLE [Survey]
(
ID int IDENTITY(1,1) NOT NULL,
UserName varchar(50) NOT NULL,
Responses varchar(max) NOT NULL,
Taken datetime NOT NULL
)
When the user clicks the submit button, a process grabs all the checkboxes that were clicked and concatenates their names into a delimited string, and stuffs that into the table along with the other fields. Essentially same as:
INSERT INTO [Survey] (UserName, Responses, Taken) VALUES ('John', 'chkSize', GetDate())
INSERT INTO [Survey] (UserName, Responses, Taken) VALUES ('Mary', 'chkSquare;chkSoft', GetDate())
INSERT INTO [Survey] (UserName, Responses, Taken) VALUES ('Steve', 'chkSize;chkYellow;chkRound', GetDate())
INSERT INTO [Survey] (UserName, Responses, Taken) VALUES ('April', 'chkRound;chkStacked;chkFiltered;chkBrown', GetDate())
Is there a way to easily go through all the "Responses" for the whole table, find all possible values, and then return them as a Unique list in their own table? i.e.:
chkBrown
chkFiltered
chkRound
chkSize
chkSoft
chkSquare
chkStacked
chkYellow

Answer 1

You can do what you want using string_split():
select s.value, count(*)
from survey su cross apply
string_split(su.responses, ';') s
group by s.value;
Here is a db<>fiddle.
The fact that you can do this does not mean that you should. You should store the responses in a separate table, with one row per response.

Answer 2

If this is just a simple one page, check box only survey, one approach is
// declare flags enum
[Flags]
public enum Checkboxes : int
{
none = 0,
chkBrown = 1,
chkFiltered = 2,
chkRound = 4,
chkSize = 8,
chkSoft = 16,
chkSquare = 32,
chkStacked = 64,
chkYellow = 128
}
// on initialize/constructor add these values to your checkbox tag
chkBrown.Tag = Checkboxes.chkBrown ;
// Add checkbox extension
public shared Checkboxes GetCode(this Checkbox cb)
{
if (cb.Checked)
return (Checkboxes)cb.Tag;
return Checkboxes.none;
}
// your db value would be
Checkboxes val = chkBrown.GetCode() | chkFiltered() . . . // list all c-boxes here
// make db field integer and save this value:
(int)val
But... again. This is only good if no changes will be required and the system is static. This seem to be homework and no long term issue. But in such cases, long term scenario is many-to-many table, where you can have multiple records for same question posted as separate record. This way, SQL search is easy
Here is working fiddle where you can also see how to set your checkbox to a value retrieved from the number
using System;
public class ClsVal// instead of checkbox
{
public bool A {get; set;}
public Checkboxes C {get; set;}
}
public static class ClsValExt
{
public static Checkboxes GetCode(this ClsVal cb)
{
if (cb.A)
return (Checkboxes)cb.C;
return Checkboxes.none;
}
}
[Flags]
public enum Checkboxes : int
{
none = 0,
chkBrown = 1,
chkFiltered = 2,
chkRound = 4,
chkSize = 8,
chkSoft = 16,
chkSquare = 32,
chkStacked = 64,
chkYellow = 128
}
public class Program
{
public static void Main()
{
var c1 = new ClsVal() {A = true, C = Checkboxes.chkBrown};
var c2 = new ClsVal() {A = true, C = Checkboxes.chkFiltered};
var c3 = new ClsVal() {A = false, C = Checkboxes.chkRound};
var c4 = new ClsVal() {A = true, C = Checkboxes.chkSize};
var x = c2.GetCode() | c1.GetCode() | c3.GetCode() | c4.GetCode();
var i = (int)x;
Console.WriteLine(i);
Console.WriteLine((x & Checkboxes.chkBrown) == Checkboxes.chkBrown); //Yes
Console.WriteLine((x & Checkboxes.chkBrown) == Checkboxes.chkYellow); // No
}
}