BorlandTalk.com Borland discussion newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  GUIDtoStr Function Goto page 1, 2, 3  Next          BorlandTalk.com Forum Index -> Delphi Databases (SQL Servers) View previous topic :: View next topic   Author Message server Guest Posted: Fri Jan 27, 2006 10:01 pm    Post subject: GUIDtoStr Function message unavailable Back to top Mark Moss Guest Posted: Fri Jan 27, 2006 10:01 pm    Post subject: Re: GUIDtoStr Function John I Tried your suggestion but it did not work, so I did a little digging and found out that even though the GUID Field is defined in MS SQL: as a 16 byte Binary Field. It is coming thru ADO as a 16 Byte TByteField. Any Ideas. Mark Moss "John Herbster" <herb-sci1_at_sbcglobal.net> wrote in message news:43da3da6$1 (AT) newsgroups (DOT) borland.com... Quote: The field is defined as a Binary field of 16 bytes Well then, I suggest that you code a readout the field's data to a variable of type TGUID (which just happens to be 16 bytes<g>) and use that as your parameter to GUIDtoString. "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote And how would I do that ? I am temped to say "Hire a computer programmer!", but I take that back. If I were doing it, I would look in Delphi IDE's Help for the methods available for the binary field in question for a method that can read binary data from the dataset field into a block of memory (i.e. a TGUID variable). On doing so I would find the "GetData" method. While looking in the help file I would check for the parameters and return values for the method and also for any Delphi examples referenced. Then I would try something like the following code. I do not know if it will work, but the compiler error messages and stepping it through at runtime it can be fixed to work. This is what I think that computer programming is all about. Regards, JohnH var GUID: TGUID; s: string; Field: TBinaryField; Field := DM.DataModule.ADOQuery2.FieldByName(CustomerID);. Assert(SizeOf(GUID) = Field .DataSize); If Field.GetData(@GUID) then s := GUIDtoString(GUID) then s := 'No data available'; Back to top John Herbster Guest Posted: Fri Jan 27, 2006 10:31 pm    Post subject: Re: GUIDtoStr Function "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote Quote: [...] I did a little digging and found out that even though the GUID Field is defined in MS SQL:as a 16 byte Binary Field, It is coming thru ADO as a 16 Byte TByteField. Mark, I think that these fields are essentially the same. So you use TBytesField instead of TBinaryField. What did you try and how did it not work? Rgds, JohnH Back to top Mark Moss Guest Posted: Fri Jan 27, 2006 10:41 pm    Post subject: Re: GUIDtoStr Function Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID'); Assert(SizeOf(Hold_GUID) = Hold_Bytes.DataSize); If Hold_Bytes.GetData(@Hold_GUID) then Hold_Customer_CustomerID := GUIDtoString(HOLD_GUID); [Error] EditCustomer.pas(240): Incompatible types: 'TBytesField' and 'TField' "John Herbster" <herb-sci1_at_sbcglobal.net> wrote in message news:43da583a (AT) newsgroups (DOT) borland.com... Quote: "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote [...] I did a little digging and found out that even though the GUID Field is defined in MS SQL:as a 16 byte Binary Field, It is coming thru ADO as a 16 Byte TByteField. Mark, I think that these fields are essentially the same. So you use TBytesField instead of TBinaryField. What did you try and how did it not work? Rgds, JohnH Back to top John Herbster Guest Posted: Fri Jan 27, 2006 11:55 pm    Post subject: Re: GUIDtoStr Function "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote Quote: Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID'); Mark, I am assuming that Hold_Bytes is of type TBytesField. FieldByName is going to return an object with visible properties of a TField object, even though the object being passed is a pointer to a TBytesField object. So we need to do a "type cast" to get to the real object so use the "as" operator: Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID') as TBytesField; It will check the type and cast it so that it can be assigned to Hold_Bytes. By the way, "Hold_Bytes" seems like a strange name for a field alias. Let us know what happens. Rgds, JohnH Quote: Assert(SizeOf(Hold_GUID) = Hold_Bytes.DataSize); If Hold_Bytes.GetData(@Hold_GUID) then Hold_Customer_CustomerID := GUIDtoString(HOLD_GUID); [Error] EditCustomer.pas(240): Incompatible types: 'TBytesField' and 'TField' Back to top Mark Moss Guest Posted: Sat Jan 28, 2006 12:13 am    Post subject: Re: GUIDtoStr Function John It Works - Thank you very very much for your help --- here is the final code. I will convert this code snippet to a procedure and post it back to the forumn. Mark Moss {--------------------------------------------------------------------------- --------------------------------} var Hold_Bytes : TBytesField; Hold_GUID : TGUID; Hold_Customer_CustomerID : String; begin Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID'); Assert(SizeOf(Hold_GUID) = Hold_Bytes.DataSize); If Hold_Bytes.GetData(@Hold_GUID) then Hold_Customer_CustomerID := GUIDtoString(HOLD_GUID) Else Hold_Customer_CustomerID := ''; end; {--------------------------------------------------------------------------- --------------------------------} "John Herbster" <herb-sci1_at_sbcglobal.net> wrote in message news:43da6be5 (AT) newsgroups (DOT) borland.com... Quote: "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID'); Mark, I am assuming that Hold_Bytes is of type TBytesField. FieldByName is going to return an object with visible properties of a TField object, even though the object being passed is a pointer to a TBytesField object. So we need to do a "type cast" to get to the real object so use the "as" operator: Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID') as TBytesField; It will check the type and cast it so that it can be assigned to Hold_Bytes. By the way, "Hold_Bytes" seems like a strange name for a field alias. Let us know what happens. Rgds, JohnH Assert(SizeOf(Hold_GUID) = Hold_Bytes.DataSize); If Hold_Bytes.GetData(@Hold_GUID) then Hold_Customer_CustomerID := GUIDtoString(HOLD_GUID); [Error] EditCustomer.pas(240): Incompatible types: 'TBytesField' and 'TField' Back to top Mark Moss Guest Posted: Sat Jan 28, 2006 1:02 am    Post subject: Re: GUIDtoStr Function Ladies / Gentlemen Below is a Function that takes a 16byte TBytesField converts it to a TGUID and converts that to the final String. Thanks for everyones help in getting this to work. Mark Moss var Hold_Bytes : TBytesField; Hold_GUIDString : String; begin Hold_Bytes := DM.DataModule1.ADOQuery2.FieldByName('CustomerID') As TBytesField; Hold_GUIDString := FGUIDtoStr(Hold_Bytes); end; {--------------------------------------------------------------------------- ---} function FGUIDtoStr(b: TBytesField):String; {--------------------------------------------------------------------------- ---} function FGUIDtoStr(b: TBytesField):String; var Hold_GUID : TGUID; begin Assert(SizeOf(Hold_GUID) = b.DataSize); If b.GetData(@Hold_GUID) then FGUIDtoStr := GUIDtoString(HOLD_GUID) else FGUIDtoStr := ''; end; {--------------------------------------------------------------------------- ---} "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote in message news:43d7c7c4 (AT) newsgroups (DOT) borland.com... Quote: Gentlemen / Ladies I am using ADO to retrieve the Data from an MS SQL Database. I use the following statement to get the data DM.DataModule.ADOQuery2.FieldByName(CustomerID).AsVariant or AsText or AsString, but I cannot get the GUIDtoStr function to work as the data types do not match TGUID. Var Hold_GUID : String; begin GUIDtoStr( DM.DataModule.ADOQuery2.FieldByName(CustomerID) ); end; How should I get this data? Mark Moss Back to top Riki Wiki Guest Posted: Sat Jan 28, 2006 4:45 pm    Post subject: Re: TOracleDataset advanced question On 25 Jan 2006 12:01:40 -0800, Guy wrote: Quote: Any ideas of other options would be appreciated. Hoi Guy You need to repost your question on the Borland news server, because the way you have posted now, it is invisibel to most people. Take a look here: <http://tinyurl.com/8m5nw> which links to <http://delphi.wikicities.com/wiki/Delphi_Newsgroups> Back to top Arthur Hoornweg Guest Posted: Sat Jan 28, 2006 7:16 pm    Post subject: Re: Upgrading a D7 ADO project to D2006 benefit in anyway? Sarah wrote: Quote: I looked at the TBetterADO help file and it appears it fixes a lot of bugs in the Delphi ADO components up to Delphi 7. Beware: there is a bug in tBetterado that only occurs under D2006 and widestring fields (it causes a gpf). -- Arthur Hoornweg (In order to reply per e-mail, please just remove the ".net" from my e-mail address. Leave the rest of the address intact including the "antispam" part. I had to take this measure to counteract unsollicited mail.) Back to top Arthur Hoornweg Guest Posted: Sat Jan 28, 2006 7:17 pm    Post subject: Re: Upgrading a D7 ADO project to D2006 benefit in anyway? Sarah wrote: Quote: Also the SQLNCLI is backward compatible with SQL Server 7 and above. Doesn't it require .NET 2.0? -- Arthur Hoornweg (In order to reply per e-mail, please just remove the ".net" from my e-mail address. Leave the rest of the address intact including the "antispam" part. I had to take this measure to counteract unsollicited mail.) Back to top Man Utd Guest Posted: Sun Jan 29, 2006 6:12 pm    Post subject: Re: Primary key How long the GUID is if represented as string? Does it include the '{', '}', and the '-' ? "Martijn Tonies" <m.tonies (AT) upscene (DOT) removethis.com> wrote in message news:43d5df66$1 (AT) newsgroups (DOT) borland.com... Quote: Oops, I just noticed Firebird only have BIGINT that is 64 bit integer. If I store the GUID as string, does it affect any sorting or searching ? Since I will use this GUID as primary key, there will quite frequent in JOIN and in WHERE clause. Yes, this affects Firebird quite a lot. Because of the index structure in Firebird, GUIDs are rather slowish. This might have improved in Firebird 2.0 due to the new index structure - feel free to ask about this in the Firebird mailinglist at Yahoogroups (see the Firebird website). Either way, there is a set of external functions available for Firebird that allows you to create reversed GUIDs, which are just as unique, but can be used faster by the database engine itself due to the index structure. Scroll down to the bottom of this page for a link: http://www.ibphoenix.com/main.nfs?a=ibphoenix&page=ibp_udf_libs -- Martijn Tonies Database Workbench - tool for InterBase, Firebird, MySQL, Oracle & MS SQL Server Upscene Productions http://www.upscene.com Database development questions? Check the forum! http://www.databasedevelopmentforum.com Back to top Bill Todd Guest Posted: Sun Jan 29, 2006 7:26 pm    Post subject: Re: Primary key Man Utd wrote: Quote: How long the GUID is if represented as string? Does it include the '{', '}', and the '-' ? Open the Delphi IDE, go into a file in the editor, press Ctrl+Shift+G and count. :) -- Bill Todd (TeamB) Back to top Guy Guest Posted: Sun Jan 29, 2006 7:42 pm    Post subject: Re: TOracleDataset advanced question Ok Thanks. I posted it thru google new groups interface? Back to top Jojo Guest Posted: Mon Jan 30, 2006 7:57 am    Post subject: Re: GUIDtoStr Function you may try this TGuidField(ADOQuery1.FieldByName('CustomerID')).AsGuid Jojo "Mike Shkolnik" <mshkolnik2002 (AT) ukr (DOT) net> wrote in message news:43d7f86b (AT) newsgroups (DOT) borland.com... Quote: If your field have the ftGUID type, you may use the .AsGUID: GUIDtoStr( DM.DataModule.ADOQuery2.FieldByName(CustomerID).AsGUID); -- With best regards, Mike Shkolnik E-mail: mshkolnik (AT) scalabium (DOT) com WEB: http://www.scalabium.com "Mark Moss" <markmoss (AT) adelphia (DOT) net> wrote in message news:43d7c7c4 (AT) newsgroups (DOT) borland.com... Gentlemen / Ladies I am using ADO to retrieve the Data from an MS SQL Database. I use the following statement to get the data DM.DataModule.ADOQuery2.FieldByName(CustomerID).AsVariant or AsText or AsString, but I cannot get the GUIDtoStr function to work as the data types do not match TGUID. Var Hold_GUID : String; begin GUIDtoStr( DM.DataModule.ADOQuery2.FieldByName(CustomerID) ); end; How should I get this data? Mark Moss Back to top Arthur Hoornweg Guest Posted: Mon Jan 30, 2006 3:06 pm    Post subject: Re: Primary key Man Utd wrote: Quote: Oops, I just noticed Firebird only have BIGINT that is 64 bit integer. If I store the GUID as string, does it affect any sorting or searching ? Store it as CHAR(3, make sure it has a proper index. Function NewGuid:String; VAR g:tguid; begin Createguid(g); result:=GuidToString (G); end; -- Arthur Hoornweg (In order to reply per e-mail, please just remove the ".net" from my e-mail address. Leave the rest of the address intact including the "antispam" part. I had to take this measure to counteract unsollicited mail.) Back to top        BorlandTalk.com Forum Index -> Delphi Databases (SQL Servers) All times are GMT Goto page 1, 2, 3  Next Page 1 of 3 Powered by phpBB © 2001, 2006 phpBB Group .