<< Click to Display Table of Contents >> Navigation:  »No topics above this level« Delphi Examples: DbiCreateInMemTable

Example 1: Create an in-memory table using a custom field descriptor.

procedure MakeInMemTable1;

const

 fldDes: array[0..2] of FLDDesc = (

   // Field 1 - ALPHA

   (iFldNum:      1;

    szName:       'ALPHA';

    iFldType:     fldZSTRING;

    iSubType:     fldUNKNOWN;

    iUnits1:      10;

    iUnits2:      0;

    iOffset:      0;

    iLen:         0;

    iNullOffset:  0;

    efldvVchk:    fldvNOCHECKS;

    efldrRights:  fldrREADWRITE),

   // Field 2 - NUMERIC

   (iFldNum:      2;

    szName:       'NUMERIC';

    iFldType:     fldFLOAT;

    iSubType:     fldUNKNOWN;

    iUnits1:      0;

    iUnits2:      0;

    iOffset:      0;

    iLen:         0;

    iNullOffset:  0;

    efldvVchk:    fldvNOCHECKS;

    efldrRights:  fldrREADWRITE),

   // Field 3 - SHORT

   (iFldNum:      3;

    szName:       'SHORT';

    iFldType:     fldINT16;

    iSubType:     fldUNKNOWN;

    iUnits1:      0;

    iUnits2:      0;

    iOffset:      0;

    iLen:         0;

    iNullOffset:  0;

    efldvVchk:    fldvNOCHECKS;

    efldrRights:  fldrREADWRITE));

var

 hIMcur   : hDBICur;

 hNilDB   : hDBIDb;

begin

 Check(dbiOpenDatabase(nil, nil, dbiREADWRITE, dbiOPENSHARED, nil, 0, nil,

  nil, hNilDB));

 Check(dbiCreateInMemTable(hNilDB, 'InMemTbl', 3, @fldDes, hIMCur));

end;

Example 2: Create an in-memory table by borrowing the field descriptor from an existing Paradox table.

The existing table is passed in the Tbl parameter.

procedure MakeInMemTable2(Tbl: TTable);

var

 TblProps : CurProps;

 PFDesc   : pFldDesc;

 hIMcur   : hDBICur;

 MemSize  : Integer;

begin

 Check(dbiGetCursorProps(Tbl.Handle, TblProps));

 MemSize := SizeOf(FldDesc) * (TblProps.iFields);

 PFDesc := AllocMem(MemSize);

try

   Check(dbiGetFieldDescs(Tbl.Handle, PFDesc));

   Check(dbiCreateInMemTable(Tbl.DBHandle, 'InMemTbl', 3, PFDesc, hIMCur));

finally

   FreeMem(PFDesc, MemSize);

end;

end;