TSQlite3Dataset doesn't raise exception when "database disk image is
malformed"
lazarus / 16-Databases

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swierzbicki · 2014-11-28 09:12

Hello,

I have an issue with an SQLite 3 database. This database was corrupted
but my function doesn't raise an exception when calling an PRAGMA
Intigrity check.
Is this expected ?

The code bellow :

Code: [Select]function TdtmMain.CleanSQLiteDatabase(const
ADatabaseName: string): string;
var
  ASQLiteConnection: TSqlite3Dataset;

begin
  if not FileExists(ADatabaseName) then
    exit;
  Result := '';

  ASQLiteConnection := TSqlite3Dataset.Create(nil);
  try
    ASQLiteConnection.FileName := ADatabaseName;
    ASQLiteConnection.ExecSQL('BEGIN TRANSACTION;');
    try
     ASQLiteConnection.ExecSQL('PRAGMA integrity_check;'); //<---
exception should be raised here
      ASQLiteConnection.ExecSQL('VACUUM;');
      ASQLiteConnection.ExecSQL('REINDEX;');
      ASQLiteConnection.ExecSQL('COMMIT;');
      Result := '';
    except
      on e: Exception do
      begin
        if Assigned(frmSplash) then
          frmSplash.lblSynchroError.Caption := e.Message;
          ASQLiteConnection.ExecSQL('ROLLBACK');
      end;
    end;
  finally
    ASQLiteConnection.Free;
  end;
end;

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swierzbicki · 2014-12-01 09:40

This is a real problem ! Is it worth to submit this ?

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Never · 2014-12-01 10:55

Are you sure about the exception?
PRAGMA integrity_check returns results if errors found and is not able
to find all kind of errors
ref: [ http://www.sqlite.org/pragma.html#pragma_integrity_check ]

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LuizAmérico · 2014-12-01 15:41

PRAGMA integrity_check returns rows, so you should do

ASQLiteConnection.Close;
ASQLiteConnection.SQL = 'PRAGMA integrity_check';
ASQLiteConnection.Open;
//verify the returned records