Compute Date and Time with SQL

anybody?

what for types are these fields (DateIn, TimeIn, DateOut, TimeOut)?
Date, time, datetime, char, varchar?
what database?

Depends on the database server that you're using. This is not a Delphi issue but a database issue. And not all databases will allow calculations with date fields.

The database is Paradox I think ("EMPLOYEE.DB") and BDE is being used perhaps.

Now the question that remains is: what are the types of the fields.

Assuming your DateX fields are of DATE type and your TimeX fields are of TIME type then your SQL may look like (Paradox):

SELECT B.badgeNo, A.fullName,
SUM(CAST((
(B.DateOut - B.DateIn) * 24
+
(B.TimeOut - B.TimeIn) * 24
) AS INTEGER))
 AS B.Total_Time FROM "EMPLOYEE.DB" AS A, "DTR.db" AS B
WHERE A.badgeNo = B.badgeNo
GROUP BY B.badgeNo, A.fullName
ORDER BY B.badgeNo

Regards, Geo

Hi everyone,

I used this to create the database

procedure TDataModule1.CreateTable_OTDTR(NameFile: string; databasePath:string);
var
 DatabaseDirectory:string;
begin
  // Create Database
  with TTable.Create(Application) do
  begin
    Active := False;
    DatabaseName := databasePath;
    TableName := NameFile;
    TableType := ttDBase;
    with FieldDefs do
    begin
      Clear;
      Add('IndexNo'        , ftString         , 15   , false);
      Add('BadgeNo'        , ftString         ,  6   , false);
      Add('ShiftCode'      , ftString         ,  5   , false);
      Add('MealRate'       , ftFloat          ,  0   , false);
      Add('DateIn'         , ftDate           ,  0   , false);
      Add('TimeIn'         , ftTime           ,  0   , false);
      Add('DateOut'        , ftDate           ,  0   , false);
      Add('TimeOut'        , ftTime           ,  0   , false);
      Add('SchedCode'      , ftString         ,  4   , false);
    end;
    CreateTable;
    with IndexDefs do
    begin
      Clear;
      Add('IndexNo'        , 'IndexNo'        , []);
    end;
    CreateTable;
    Free;
  end;
end;

This cause a Type mismatch error

 wwQuery1.SQL.Add('SELECT B.BadgeNo, A.EmpName,SUM((((B.DateOut - B.DateIn) * 24)+((B.TimeOut - B.TimeIn) * 24))) AS B.Total_Time FROM '+main.DB_Employee+' AS A, '+main.DB_OTDTR+' AS B');
 wwQuery1.SQL.Add('WHERE A.BadgeNo = B.BadgeNo');
 wwQuery1.SQL.Add('GROUP BY B.BadgeNo, A.EmpName, B.DateOut');
 wwQuery1.SQL.Add('ORDER BY B.BadgeNo');
 wwQuery1.ExecSQL;
 wwQuery1.Open;
 Browse.DataSource:=wwDataSource2;

My database is not a paradox.

Please, follow the exact SQL statement I've provided:
- I used CAST AS INTEGER for the SUM and you didn't.
- Also B.DateOut cannot be in the GROUP BY because you don't have such a column in your SELECT list.
- Remove wwQuery1.ExecSQL; - this is wrong !
- Browse.DataSource:=wwDataSource2; should be before wwQuery1.Open; if this is something related to the query.

Regards, Geo

The first source code you've posted was first applied but it failed on that "CAST" part.
That is why i removed that area.

wwQuery1.DatabaseName:=main.Database_Path;
 wwQuery1.SQL.Clear;

 wwQuery1.SQL.Add('SELECT B.BadgeNo, A.EmpName,');
 wwQuery1.SQL.Add('SUM(CAST((');
 wwQuery1.SQL.Add('(B.DateOut - B.DateIn) * 24');
 wwQuery1.SQL.Add('+');
 wwQuery1.SQL.Add('(B.TimeOut - B.TimeIn) * 24');
 wwQuery1.SQL.Add(') AS INTEGER))');
 wwQuery1.SQL.Add(' AS B.Total_Time FROM "'+main.DB_Employee+'" AS A, "'+main.DB_OTDTR+'" AS B');
 wwQuery1.SQL.Add('WHERE A.BadgeNo = B.BadgeNo');
 wwQuery1.SQL.Add('GROUP BY B.BadgeNo, A.EmpName');
 wwQuery1.SQL.Add('ORDER BY B.BadgeNo');
 wwQuery1.Open;
 Browse.DataSource:=wwDataSource2;

STILL HAVING PROBLEM.
"Type Mismatch in expression." <--- error

Your database is not Paradox. OK. It's DBASE then, I guess. Is that right? Please, tell me what it is (not what it isn't). I'm confused because you're naming your tables .DB (paradox) but setting TableType to ttDBase later on.

If your db is DBASE then ftTime fields are CHAR(11) actually not TIME (as they would be in Paradox). That's why you can't substract them directly. You should use:

(CAST(B.TimeOut AS TIME) - CAST(B.TimeIn AS TIME)) * 24

instead of

(B.TimeOut - B.TimeIn) * 24

That's all.

Regards, Geo

wwQuery1.DatabaseName:=main.Database_Path;
 wwQuery1.SQL.Clear;

 wwQuery1.SQL.Add('SELECT B.BadgeNo, A.EmpName,');
 wwQuery1.SQL.Add('SUM(CAST((');
 wwQuery1.SQL.Add('(CAST(B.DateOut AS TIME) - CAST(B.DateIn AS TIME)) * 24');
 wwQuery1.SQL.Add('+');
 wwQuery1.SQL.Add('(CAST(B.TimeOut AS TIME) - CAST(B.TimeIn AS TIME)) * 24');
 wwQuery1.SQL.Add(') AS INTEGER))');
 wwQuery1.SQL.Add(' AS B.Total_Time FROM "'+main.DB_Employee+'" AS A, "'+main.DB_OTDTR+'" AS B');
 wwQuery1.SQL.Add('WHERE A.BadgeNo = B.BadgeNo');
 wwQuery1.SQL.Add('GROUP BY B.BadgeNo, A.EmpName');
 wwQuery1.SQL.Add('ORDER BY B.BadgeNo');
 wwQuery1.Open;

I already used the "CAST" but
STILL HAVING PROBLEM.
"Type Mismatch in expression." <--- error

I'm sorry to hear that. Both versions (paradox and dbase) work just fine here.

Here is the complete code that i used. Hope this will help, or maybe i have a problem with my query table used.

I used TQuery.


procedure TSubsidy.Button2Click(Sender: TObject);
begin
 wwQuery1.DatabaseName:=main.Database_Path;
 wwQuery1.SQL.Clear;

 wwQuery1.SQL.Add('SELECT B.BadgeNo, A.EmpName,');
 wwQuery1.SQL.Add('SUM(((');
 wwQuery1.SQL.Add('((B.DateOut) - (B.DateIn)) * 24');
 wwQuery1.SQL.Add('+');
 wwQuery1.SQL.Add('((B.TimeOut) - (B.TimeIn)) * 24');
 wwQuery1.SQL.Add(')))');
 wwQuery1.SQL.Add('AS B.Total_Time FROM "'+main.DB_Employee+'" AS A, "'+main.DB_OTDTR+'" AS B');
 wwQuery1.SQL.Add('WHERE A.BadgeNo = B.BadgeNo');
 wwQuery1.SQL.Add('GROUP BY B.BadgeNo, A.EmpName');
 wwQuery1.SQL.Add('ORDER BY B.BadgeNo');
 wwQuery1.Open;
 Browse.DataSource:=wwDataSource2;
end;


in my datamodule

procedure TDataModule1.CreateTable_OTDTR(NameFile: string; databasePath:string);
var
 DatabaseDirectory:string;
begin
  // Create Database
  with TTable.Create(Application) do
  begin
    Active := False;
    DatabaseName := databasePath;
    TableName := NameFile;
    TableType := ttDBase;
    with FieldDefs do
    begin
      Clear;
      Add('IndexNo'        , ftString         , 15   , false);
      Add('BadgeNo'        , ftString         ,  6   , false);
      Add('ShiftCode'      , ftString         ,  5   , false);
      Add('MealRate'       , ftFloat          ,  0   , false);
      Add('DateIn'         , ftDate           ,  0   , false);
      Add('TimeIn'         , ftFloat          ,  0   , false);
      Add('DateOut'        , ftDate           ,  0   , false);
      Add('TimeOut'        , ftFloat          ,  0   , false);
      Add('SchedCode'      , ftString         ,  4   , false);
    end;
    CreateTable;
    with IndexDefs do
    begin
      Clear;
      Add('IndexNo'        , 'IndexNo'        , []);
    end;
    CreateTable;
    Free;
  end;
end;

Wow, time fields have become of float type now! Let it be...

Try changing:
wwQuery1.SQL.Add('((B.TimeOut) - (B.TimeIn)) * 24');
to
wwQuery1.SQL.Add('CAST(((B.TimeOut) - (B.TimeIn)) * 24) AS INTEGER');

Regards, Geo

i have received "Invalid use of token ")""

Please see this code. I wonder whats wrong with this.

 wwQuery1.DatabaseName:=main.Database_Path;
 wwQuery1.SQL.Clear;

 wwQuery1.SQL.Add('SELECT B.BadgeNo, A.EmpName,');
 wwQuery1.SQL.Add('SUM(((');
 wwQuery1.SQL.Add('((B.TimeOut) - (B.TimeIn)) * 24');
 wwQuery1.SQL.Add('+');
 wwQuery1.SQL.Add('CAST(((B.TimeOut) - (B.TimeIn)) * 24) AS INTEGER');
 wwQuery1.SQL.Add(')))');
 wwQuery1.SQL.Add('AS B.Total_Time FROM "'+main.DB_Employee+'" AS A, "'+main.DB_OTDTR+'" AS B');
 wwQuery1.SQL.Add('WHERE A.BadgeNo = B.BadgeNo');
 wwQuery1.SQL.Add('GROUP BY B.BadgeNo, A.EmpName');
 wwQuery1.SQL.Add('ORDER BY B.BadgeNo');
 wwQuery1.Open;
 Browse.DataSource:=wwDataSource2;

Thank you very much geobul, For you price, i've raised the points to 200.
Youre the Master of Delphi

Thank you very much :-)

BTW the third line in my last comment above is wrong. It should be:
wwQuery1.SQL.Add('(B.DateOut - B.DateIn) * 24');

Regards, Geo