private static IEnumerable <MigrationOperation> DetectHistoryRebuild(IEnumerable <MigrationOperation> operations)
{
var enumerator = operations.GetEnumerator();
while (enumerator.MoveNext())
{
var sequence = HistoryRebuildOperationSequence.Detect(enumerator);
yield return((sequence == null) ? enumerator.Current : sequence);
}
}
private static IEnumerable <MigrationOperation> DetectHistoryRebuild(
IEnumerable <MigrationOperation> operations)
{
DebugCheck.NotNull(operations);
var enumerator = operations.GetEnumerator();
while (enumerator.MoveNext())
{
var sequence = HistoryRebuildOperationSequence.Detect(enumerator);
yield return(sequence ?? enumerator.Current);
}
}
private void Generate(HistoryRebuildOperationSequence sequence)
{
DebugCheck.NotNull(sequence);
var createTableOperationSource = sequence.DropPrimaryKeyOperation.CreateTableOperation;
var createTableOperationTarget = ResolveNameConflicts(createTableOperationSource);
var renameTableOperation = new RenameTableOperation(
createTableOperationTarget.Name, HistoryContext.DefaultTableName);
using (var writer = Writer())
{
WriteCreateTable(createTableOperationTarget, writer);
writer.WriteLine();
// Copy the data from the original table into the new table.
writer.Write("INSERT INTO ");
writer.WriteLine(Name(createTableOperationTarget.Name));
writer.Write("SELECT ");
var first = true;
foreach (var column in createTableOperationSource.Columns)
{
if (first)
{
first = false;
}
else
{
writer.Write(", ");
}
writer.Write(
(column.Name == sequence.AddColumnOperation.Column.Name)
? Generate((string)sequence.AddColumnOperation.Column.DefaultValue)
: (column.Type == PrimitiveTypeKind.String)
? "LEFT(" + Name(column.Name) + ", " + column.MaxLength + ")"
: Name(column.Name));
}
writer.Write(" FROM ");
writer.WriteLine(Name(createTableOperationSource.Name));
writer.Write("DROP TABLE ");
writer.WriteLine(Name(createTableOperationSource.Name));
WriteRenameTable(renameTableOperation, writer);
Statement(writer);
}
}
