[SOLVED] SQLite: Selected fields on result
lazarus / 16-Databases

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totya · 2023-02-23 10:17

Hi!

For example I have a simple query (draft untested):

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i SELECT    
  a.x1 AS "a-x1",        a.x2 AS "a-x2",        b.x1 AS "b-x1",      
b.x2 AS "b-x2"FROM        a,        bWHERE        a.x1 = b.x1       
AND a.x2 <> b.x2 
it's simple, but I want to see only the a.x1, a.x2, and b.x2 fields in
the dbgrid (except b.x1).

Is it possible anyhow with SQLite command or only solution with add
required columns to the dbrig manually?

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dseligo · 2023-02-23 10:28

With SQL you can leave out columns you don't need:
Code: MySQL  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i SELECT    
  a.x1 AS "a-x1",        b.x1 AS "b-x1",        b.x2 AS "b-x2"FROM   
   a,        bWHERE        a.x1 = b.x1        AND a.x2 <> b.x2
If you need that column, beside manually adding columns to DBGrid, you
could add it/remove it programmatically.
Something like this:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i function
GetDBGridColumn(aDBGrid:TDBGrid; aFieldName:string):TColumn;var
iColidx:integer;begin  for iColidx:=0 to aDBGrid.Columns.Count-1 do  
if aDBGrid.Columns[iColidx].FieldName=aFieldName then begin     
Result:=aDBGrid.Columns[iColidx];      Exit;    end;  Result :=
nil;end; var column: TColumn; ... SQLQuery1.SQL.Text :=
'...';SQLQuery1.Open; // E.g. DBGrid1 connect to SQLQuery1.column :=
GetDBGridColumn(DBGrid1, 'a-x2');If column <> nil then  column.Visible
:= False;

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totya · 2023-02-23 10:44

Quote from: dseligo on February 23, 2023, 11:28:10 amWith SQL you can
leave out columns you don't need:
Wow, thank you for the quick answers! I tried to the first solution,
it's working!

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Zvoni · 2023-02-23 11:33

hrhrhrhr
Code: SQL  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i SELECT    
  a.x1 AS "a-x1",        a.x2 AS "a-x2",        /*b.x1 AS "b-x1",*/  
    b.x2 AS "b-x2"FROM        a,        bWHERE        a.x1 = b.x1    
  AND a.x2 <> b.x2

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totya · 2023-02-23 12:58

Quote from: Zvoni on February 23, 2023, 12:33:33 pmhrhrhrhr
Code: SQL  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i SELECT    
  a.x1 AS "a-x1",        a.x2 AS "a-x2",        /*b.x1 AS "b-x1",*/  
    b.x2 AS "b-x2"FROM        a,        bWHERE        a.x1 = b.x1    
  AND a.x2 <> b.x2 
I got already good answer, the point is that the field (column) you
don't want must be omitted from the select, but yes, the good answer
exactly what you wrote.

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Zvoni · 2023-02-23 14:52

Quote from: totya on February 23, 2023, 01:58:57 pmQuote from: Zvoni
on February 23, 2023, 12:33:33 pmhrhrhrhr
Code: SQL  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i SELECT    
  a.x1 AS "a-x1",        a.x2 AS "a-x2",        /*b.x1 AS "b-x1",*/  
    b.x2 AS "b-x2"FROM        a,        bWHERE        a.x1 = b.x1    
  AND a.x2 <> b.x2 
I got already good answer, the point is that the field (column) you
don't want must be omitted from the select, but yes, the good answer
exactly what you wrote.
It's a Trick i developed for myself, when testing SQL-Statements.
Just comment out, what you don't need after the initial tests