🚀 go-pugleaf

Hi,

Is there a clever way of designing a flexible SQL Statement through ADO?

I have a database that is in the shape of the following
Column 1: Date
Column 2: DataWhateverColumn1
Column 3: DataWhateverColumn2
Column 4: DataWhateverColumn3
Column 5: DataWhateverColumn4
Column 6: DataWhateverColumn5
etc...
Up to 30

<To Break Things Down Simplistically>
I'm using a TDataModule.
I Have a TADOQuery Associated with a TDatasource.

The SQL Statement TString in the TADOQuery is:
Select *
From mySQLTableData
Where Date>=:InputStartDate and Date<=:InputEndDate

The corresponding TParameter(s) are
InputStartDate
InputEndDate

My problem comes in where:
1. I need only certain data columns ("X" Combinations)

So my SQL Query could look like
Select Date, DataWhateverColumn1
From mySQLTableData
Where Date>=:InputStartDate and Date<=:InputEndDate

or 
Select Date, DataWhateverColumn2
From mySQLTableData
Where Date>=:InputStartDate and Date<=:InputEndDate

or 
Select Date, DataWhateverColumn1, DataWhateverColumn2
From mySQLTableData
Where Date>=:InputStartDate and Date<=:InputEndDate

I Use the Following Method:

TADOQuery1->Close();
TADOQuery1->SQL->Clear();

TADOQuery1->SQL->ADD("Select Date, DataWhateverColumn1 ")
TADOQuery1->SQL->ADD("From mySQLTableData ");
TADOQuery1->SQL->ADD("Where Date>=:InputStartDate ");
TADOQuery1->SQL->ADD("and Date<=:InputEndDate ");

TADOQuery1->SQL->Parameters->ParamByName("InputStartDate")->Value = HappyStartDate;
TADOQuery1->SQL->Parameters->ParamByName("InputEndDate")->Value = HappyEndDate;

TADOQuery1->Open();

Unfortunately, I discovered that it is not possible to design a flexible SELECT statement.

AnsiString DynamicFlexSQLStmt = "SELECT Date " + ""... (Whatever I add for Column Selections)

I cannont use TADOQuery1->SQL->Add(":MyFlexibleSQLStmt");
TADOQuery1->SQL->Parameters->ParamByName("MyFlexibleSQLStmt")->Value = DynamicFlexSQLStmt;

There must be a way where I can dynamically bind a SQL SELECT Statement to an ADOQuery? Shouldn't there be one? Other than the SQL->ADD() method which is rather limited.

Is there something even more advanced that I should do?

The alternative is a frightenly large set of switch statements.
case whatever:
   SQL->Add("Select This")
next case:
   SQL->Add("Select That")
next case:
   SQL->ADD("Select This, That")
... more combinations

But being a programmer... it's obvious that there's a better way, but I just don't know what it is yet.


Thanks,
Heinz.