Currently I have something like but I'm unable to retrieve my data from the dataset when it has single quote in the data
procedure TForm1.AfterConstruction;
begin
inherited;
cdsMain.FieldDefs.Add('ItemCode', ftWideString, 20);
cdsMain.CreateDataSet;
cdsDetail.FieldDefs.Add('ItemCode', ftWideString, 20);
cdsDetail.FieldDefs.Add('Project', ftWideString, 20);
cdsDetail.CreateDataSet;
var S := '6x8''''';
cdsMain.AppendRecord([S]);
cdsDetail.AppendRecord([S, 'P01']);
cdsDetail.AppendRecord([S, 'P02']);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
if FDConnection1.Connected then
FDConnection1.Close;
if FDLocalSQL1.Active then
FDLocalSQL1.Active := False;
FDLocalSQL1.Active := True;
FDQuery1.Open('SELECT A.ItemCode, B.Project FROM Main A INNER JOIN Detail B ON (A.ItemCode=B.ItemCode)');
end;
My expected result are
ItemCode Project
6x8' P01
6x8' P02
The error I get when I use var S := '6x8''''
Source code
From what I can deduce from the source files, there's a bug in FireDAC in this case. If I eliminate the ON clause in the SQL, it works, even with an ASCII Single-Quote (#39). If I replace the ASCII Single-Quote (#39) with the UNICODE Single-Quote (#8216) or remove it altogether, it works.
It seems like the parser for TFDLocalSQL (I think) has a bug when it tries to resolve the ON clause and there's an ASCII Single-Quote involved.
You should report the error to Embarcadero at https://quality.embarcadero.com, including your source code and an explanation.
Related
We are in the process of upgrading one of our projects from Delphi XE to XE8. Our audit code makes use of a TIMESTAMP field in a MSSQL (2012 in this instance) database and selects from a table using this as a parameter in the WHERE clause.
We now are no longer getting any results running the following code:
procedure TForm2.Button1Click(Sender: TObject);
begin
ADODataset1.CommandText := 'SELECT * FROM CURRENCYAUDIT';
ADODataset2.CommandText := 'SELECT * FROM CURRENCYAUDIT WHERE Audit_Timestamp = :Timestamp';
ADODataset2.Parameters.Refresh;
ADODataset1.Open;
if ADODataset1.FieldByName('audit_timestamp').IsNull or ADODataset1.IsEmpty then
begin
showmessage('nothing to compare');
end;
ADODataset2.Parameters[0].Value := ADODataset1.FieldByName('audit_timestamp').Value;
ADODataset2.Open;
caption := inttostr(ADODataset2.RecordCount);
end;
Where CurrencyAudit is any old MSSQL table containing an notnull timestamp audit_timestamp field.
The caption of the form is 0 with no message shown.
Any idea how I can get this to work? Tried AsString (nonsense string, 0 results), AsSQLTimestamp (parameter doesn't accept) and AsBytes (0 return). Unfortunately the return of the .Value only evalates as 'variant array of byte' which isn't helpful to visualise/see what it is.
Edit: Running it as .AsBytes and viewing that in the debugger I can see that the XE verison is returning 0,0,0,0,0,8,177,22 whereas the XE8 is returning 17,32,0,0,0,0,0,0. Checking other fields of the (real) database shows the record is the same. Looks like a bug in reading TIMESTAMPs from the DB
I'm using two AdoQueries. The following works fine for me in D7, correctly returning 1 row in AdoQuery2, but 0 records in XE8, so obviously has the same XE8 problem as you've run into.
var
S : String;
V : Variant;
begin
AdoQuery1.Open;
S := AdoQuery1.FieldByName('ATimeStamp').AsString;
V := AdoQuery1.FieldByName('ATimeStamp').AsVariant;
Caption := S;
AdoQuery2.Parameters.ParamByName('ATimeStamp').Value := V;
AdoQuery2.Open;
Just for testing, I'm running my AdoQuery1 and AdoQuery2 against the same server table.
Update : I've got a similar method to the one in your answer working that avoids the need for your Int64ToByteArray, at the expense of some slightly messier (and less efficient) Sql, which may not be to your taste.
In my source AdoQuery, I have this Sql
select *, convert(int, atimestamp) as inttimestamp from timestamps
and in the destination one
select * from timestamps where convert(int, atimestamp) = :inttimestamp
which of course avoids the need for a varBytes parameter on the second AdoQuery, since one can pick up the integer version of the timestamp column value and assign it to the inttimestamp param.
Btw, in your original q
if ADODataset1.FieldByName('audit_timestamp').IsNull or ADODataset1.IsEmpty then
the two expressions would better be written the other way around. Unless ADODataset1 has persistent fields, if it contains no records when opened, referring to the audit_timestamp should raise a "Field not found" exception.
It appears that EMBT have broken the conversion of a TIMESTAMP into a byte array. The XE version of the bytearray is correct and manually pulling down the data as an int64 and then building the bytearray by hand (is there an out-of-the-box function for this?) and using that as the parameter works in XE8.
I've no idea whether this is a similar issue with other binary data types. Hope not!
Working code:
procedure TForm2.Button1Click(Sender: TObject);
var
TestArray: TArray<Byte>;
j: integer;
function Int64ToByteArray(const inInt: uint64): TArray<Byte>;
var
i: integer;
lInt: int64;
begin
SetLength(result, 8);
lInt := inint;
for i := low(result) to high(result) do
begin
result[high(result)-i] := lInt and $FF;
lInt := lInt shr 8;
end;
end;
begin
ADODataset1.CommandText := 'SELECT *, cast(audit_timestamp as bigint) tmp FROM CURRENCYAUDIT';
ADODataset2.CommandText := 'SELECT * FROM CURRENCYAUDIT WHERE Audit_Timestamp = :Timestamp';
ADODataset2.Parameters.Refresh;
ADODataset1.Open;
if ADODataset1.FieldByName('audit_timestamp').IsNull or ADODataset1.IsEmpty then
begin
showmessage('nothing to compare');
end;
ADODataset2.Parameters[0].Value := Int64ToByteArray(ADODataset1.FieldByName('tmp').asInteger);
ADODataset2.Open;
caption := inttostr(ADODataset2.RecordCount);
end;
I've also checked this going down my entire (real) table and ensuring all other fields match to make sure it's not a one-off!
I'll raise a ticket with EMBT for them to sit on and ignore for 5 years ;-)
https://quality.embarcadero.com/browse/RSP-11644
I am trying to write a program to read a long list of book(1000 books),isbn etc
but when the program runs, it shows range overrun
the format of txt is
1
1234567890
ABC book
peter
20
2
1234567896
...
the code is:
const maxbk=1000;
type bookrecord = record
book_no:string;
isbn:string;
book_name:string;
author:string;
borrowed:string;
end;
var booklist : array[1..maxbk] of bookrecord;totalbook:integer;
procedure readbooklist(var bklist:array of bookrecord;var totalbk:integer);
var f:text;temp:string;code:integer;
begin
totalbk:=0;
assign(f,'bklist.txt');
reset(f);
while not eof(f) do
begin
readln(f,bklist[totalbk+1].book_no);
readln(f,bklist[totalbk+1].isbn);
readln(f,bklist[totalbk+1].book_name);
readln(f,bklist[totalbk+1].author);
readln(f,bklist[totalbk+1].borrowed);
totalbk:=totalbk+1;
end;
close(f);
writeln('read file done');
end;
begin
readbooklist(booklist,totalbook);
end.
who can help to fix the problem??
I think the problem is in your handling of the array parameter. Try this (highlighted in bold are the changes I've added):
const maxbk=1000;
type bookrecord = record
book_no:string;
isbn:string;
book_name:string;
author:string;
borrowed:string;
end;
var booklist : array[1..maxbk] of bookrecord; totalbook:integer;
procedure readbooklist(var bklist:array of bookrecord;var totalbk:integer);
var f:text;temp:string;code:integer;
begin
totalbk:=Low(bklist);
assign(f,'bklist.txt');
reset(f);
while not eof(f) do
begin
readln(f,bklist[totalbk].book_no);
readln(f,bklist[totalbk].isbn);
readln(f,bklist[totalbk].book_name);
readln(f,bklist[totalbk].author);
readln(f,bklist[totalbk].borrowed);
totalbk:=totalbk+1;
end;
totalbk := totalbk - Low(bklist);
close(f);
writeln('read file done');
end;
begin
readbooklist(booklist,totalbook);
end.
Also, a few choice spaces would help with readability (like a space after each comma and around assignment operators).
Note, too, that your code (and the changed code I'm providing) don't check for incomplete records in your input text file or properly check for blank lines, etc (e.g., invalid book_no values). You should attempt to add some code which makes it a little more resilient to problems in the input file. As others have pointed out, there are probably better ways to structure the input and read it as well.
I am trying to pass in a null value to a TSQLDataset parameter. The query has the form:
Query_text:='MERGE INTO [Table]
USING (VALUES (:A,:B)) AS Source (Source_A, Source_B)
....
WHEN MATCHED THEN
UPDATE SET A = :A
WHEN NOT MATCHED THEN
INSERT(A, B) VALUES (:A,:B);
SQL_dataset.CommandType:=ctQuery;
SQL_dataset.CommandText:=Query_text;
SQL_dataset.ParamByName('A').AsString:='A';
SQL_dataset.ParamByName('B').AsString:={ COULD BE NULL, OR A STRING };
SQL_dataset.ExecSQL;
Parameter B is nullable, but is also a foreign key. If the user enters something in this field, then B must be validated against values in another table. If it is blank then I want it to be ignored. I was passing in '', but this obviously produces a FK violation error.
I tried:
SQL_dataset.ParamByName('B').Value:=Null;
..but then I get a "dbexpress driver does not support the tdbxtypes.unknown data type" error.
I also tried:
SQL_dataset.ParamByName('B').DataType:=ftVariant;
SQL_dataset.ParamByName('B').Value:=Null;
..but then got "dbexpress driver does not support the tdbxtypes.variant data type" error.
Not sure what I am doing wrong, any help would be appreciated. I am currently drawing up a parameter list based on whether the string is populated or not, and this works well; it's just a bit clunky (in my actual query) as there are quite a few parameters to validate.
I am using Delphi XE4 and SQL server 2012.
Update:
Thanks for all the help, your suggestions were right all along, it was something else that produced that 'dbexpress driver' error. I was creating a 'flexible' parameter list in an effort to get around my problem, and this caused the exception:
Parameter_string:='';
If B<>'' then Parameter_string:='B = :B,'
Query_text:='MERGE ...'
'...'
'UPDATE SET A = :A, '+Parameter_string+' C = :C' ....
... the idea being that if B is blank then the parameter won't be 'listed' in the query.
This doesn't work, or my implementation of it doesn't work (not sure why, I'm obviously missing a step somewhere).
Anyway, the working code:
Query_text:='MERGE ...'
'...'
'UPDATE SET A = :A, B = :B, C = :C' ....
SQL_dataset.CommandType:=ctQuery;
SQL_dataset.CommandText:=Query_text;
If B<>'' then
begin
SQL_dataset.ParamByName('B').AsString:='B';
end
else
begin
SQL_dataset.ParamByName('B').DataType:=ftString;
SQL_dataset.ParamByName('B').Value:=Null;
end;
what about:
SQL_dataset.ParamByName('B').Clear;
If I recall correctly, the db-null equivalent in Delphi is Variants.Null
Usual approach would be using parameters once per query and assign the appropriate datatype.
Value may be assigned to NULL.
var
Query_text:String;
begin
Query_text:='Declare #A varchar(100) ' // or e.g. integer
+#13#10'Declare #B varchar(100)'
+#13#10'Select #A=:A'
+#13#10'Select #B=:B'
+#13#10'Update Adressen Set Vorname=#A,Strasse=#B where Name=#B';
SQL_dataset.CommandType := ctQuery;
SQL_dataset.CommandText := Query_text;
SQL_dataset.Params.ParseSQL(SQL_dataset.CommandText,true);
Showmessage(IntToStr(SQL_dataset.Params.Count));
SQL_dataset.ParamByName('B').DataType := ftString;
SQL_dataset.ParamByName('B').Value := 'MyText';
SQL_dataset.ParamByName('A').DataType := ftString; // or e.g. ftInteger
SQL_dataset.ParamByName('A').Value := NULL;
SQL_dataset.ExecSQL;
end;
I'm trying to write bits of code to a Microsoft access database from Delphi. I'm getting data from a TStringGrid. The first column has the ItemID, and the 2nd column has the Quantity. I'd like it to loop through the TStringGrid and save each row as a reperate row in my database and also save the Order ID with it on every column (The order ID stays the same for each order so that doesn't need to change) .
I'm getting an error when running which says
"Project Heatmat.exe raised an exception class EVarientInvalidArgError with message 'Invalid Argument'. Process Stopped."
I can't figure out why it's giving me this error, and as you can probably see i'm not very good at coding yet. Any help would be appreciated!
Thank you.
procedure TCreateNewOrder.btnSaveClick(Sender: TObject);
var
intNumber, count : integer;
begin
Count:= 0;
if messagedlg ('Are you sure?', mtWarning, [mbyes, mbno], 0) = mryes then
begin
with HeatmatConnection.HeatmatDatabase do
begin
intNumber:= TBLOrder.RecordCount;
TBLOrder.Append;
TBLOrder['CustomerID']:= CompanyName.ItemIndex+1;
TBLOrder['OrderID']:= intNumber +1;
for count:= 1 to StringGrid1.RowCount-1 do
begin
TBLOrderedItem.Append;
TBLOrderedItem['OrderID']:= intNumber+1;
TBLOrderedItem['ItemID']:= StringGrid1.Cells[1, count];
TBLOrderedItem['Quantity']:= StringGrid1.Cells[2, count];
TBLOrderedItem.Post;
end;
end;
end;
end;
TStringGrid cells are strings. trying to assign a string directly to a numeric field will raise an Exception.
So a good practice is to assign values to database fields via AsString, AsInteger, AsBoolean etc... this will make the correct conversion.
In your code use:
TBLOrderedItem.FieldByName('ItemID').AsString := StringGrid1.Cells[1, count];
The same is true for Quantity.
To assign an Integer value use:
TBLOrderedItem.FieldByName('OrderID').AsInteger := intNumber + 1;
BTW, you are forgetting TBLOrder.Post i.e:
....
TBLOrder.Append;
TBLOrder.FieldByName('CustomerID').AsInteger := CompanyName.ItemIndex + 1;
TBLOrder.FieldByName('OrderID').AsInteger := intNumber + 1;
TBLOrder.Post;
...
Finally, I would also suggest to rename TBLOrder to tblOrder so that it's name wont imply that it is a Type.
I have a problem with a old Delphi system, this system insert data into a SQL Server table.
After 10 years change a field of the table from 100 to 255 chars long.
The system select all the registris of the table, and put them on an other table after a transformation. That works fine.
The problems are when the system update a field.
That show me the error
EDBEngineError with message 'Couldn't perform the edit because another user changed the record.
sConsulta:='SELECT * FROM cuentas WHERE (WALL= 2) AND (SEND_DATE = '01/01/1970')';
m_oQryLeg.Close;
m_oQryLeg.SQL.Clear;
m_oQryLeg.SQL.Add(sConsulta);
m_oQryLeg.Open;
m_oTblNov.Close;
m_oTblNov.TableName:='des_table';
m_oTblNov.Open;
with m_oTblNov do
begin
while (not m_oQryLeg.EOF) do
begin
Insert;
FieldbyName('COD_HOME').AsString:= m_oQryLeg.FieldByName('USR_HOME').AsString;
(...)
Post;
m_oQryLeg.Edit;
m_oQryLeg.FieldByName('SEND_DATE').AsDateTime:= Date; //<-- HERE THE ERROR
m_oQryLeg.Post;
m_oQryLeg.First;
m_oQryLeg.MoveBy(i);
inc(i);
end;
end;
m_oTblNov.Close;
m_oQryLeg.Close;
UpdateMode: upWhereAll
cuentas table:
NUM_SOL nvarchar 6 *PK
WALL tinyint 1
SEND_DATE smalldatetime 4
OBS_CRED nvarchar 255
FLCC real 4
STREET nvarchar 30
You're trying to update a query you're using on a table you're editing at the same time, and it's not going to work.
Since you know you're going to insert every row from the query into m_oTblNov, why not just do it like this instead?
sConsultaSELECT :='SELECT * FROM cuentas';
sConsultaUPDATE := 'UPDATE cuentas SET Send_Date = :New_Date';
// Separate WHERE so you can use it twice. Note the leading space
// between the first ' and WHERE.
sWhere := ' WHERE (WALL = 2) and (SEND_DATE = ''01/01/1970'')';
m_oQryLeg.Close;
m_oQryLeg.SQL.Text := sConsulta + sWhere;
m_oQryLeg.Open;
m_oTblNov.Close;
m_oTblNov.TableName:='des_table';
m_oTblNov.Open;
with m_oTblNov do
begin
while (not m_oQryLeg.EOF) do
begin
Insert;
FieldbyName('COD_HOME').AsString:= m_oQryLeg.FieldByName('USR_HOME').AsString;
(...)
Post;
// Don't run these any more. See below.
// m_oQryLeg.Edit;
// m_oQryLeg.FieldByName('SEND_DATE').AsDateTime:= Date; //<-- HERE THE ERROR
// m_oQryLeg.Post;
m_oQryLeg.First;
m_oQryLeg.MoveBy(i);
inc(i);
end;
end;
m_oTblNov.Close;
m_oQryLeg.Close;
m_oQryLeg.SQL.Text := sConsultaUPDATE + sWHERE;
m_oQryLeg.ParamByName('New_Date').AsDateTime := Date;
try
m_oQryLeg.ExecSQL;
finally
m_oQryLeg.Close;
end;
The problem here is that your object is trying to refresh the row from the database to make sure nothing has changed and more than likely the object truncated or rounded some value that is causing the refresh to return no rows.
This could be caused by either a float value being truncated or some other value being off.
if you don't/can't change that column to fix this issue I would advise changing to either upWhereChanged or upWhereKeyOnly.
Given that dates are treated as doubles in most windows databases, I would think that upWhereKeyOnly would be best.
EDIT:
After looking at your table, it may have to do with the fact you are using a single based smalldatetime. Delphi treats all DateTime data as a double and the conversion back and forth may be causing small rounding issues.