internal static void Execute(QuerySource[] sources, string queryText, IWriter writer,
ParallelOptions options, bool dumpSql, Dictionary <string, object> parameters)
{
RowAccessor rowAccessor = null;
var locker = new object();
var runTimestamp = DateTime.Now;
var writeStarted = false;
try
{
Parallel.ForEach(sources, options, (source, state) =>
{
try
{
if (state.ShouldExitCurrentIteration)
{
return;
}
var sql = Translate(source, queryText, runTimestamp);
if (dumpSql)
{
Console.Out.WriteLine("\r\n[{0}]\r\n{1}\r\n====>\r\n{2}",
source.ConnectionString, queryText, sql);
}
if (state.ShouldExitCurrentIteration)
{
return;
}
var db = new PostgreeSqlDatabase(source.ConnectionString);
db.Execute(sql, parameters, c =>
{
if (state.ShouldExitCurrentIteration)
{
return;
}
using (var reader = (NpgsqlDataReader)c.ExecuteReader())
{
if (state.ShouldExitCurrentIteration)
{
return;
}
var columns = DatabaseHelpers.GetColumns(reader);
lock (locker)
if (rowAccessor == null)
{
rowAccessor = new RowAccessor(columns);
writer.BeginWrite(columns);
writeStarted = true;
}
else
{
DatabaseHelpers.CheckColumnsAreEqual(rowAccessor.Columns, "original", columns, "current");
}
if (state.ShouldExitCurrentIteration)
{
return;
}
while (reader.Read())
{
if (state.ShouldExitCurrentIteration)
{
return;
}
lock (locker)
{
rowAccessor.Reader = reader;
writer.Write(rowAccessor);
}
}
}
});
}
catch (Exception e)
{
const string messageFormat = "error has occurred for database [{0}]";
throw new InvalidOperationException(
string.Format(messageFormat, source.ConnectionString), e);
}
});
}
finally
{
if (writeStarted)
{
writer.EndWrite();
}
}
}