private void GenerateRange(IEnumerable <RangeHPartitioningAttributeDefinition> attributePartitions, List <RangeHPartitionAttributeDefinition> partitionParts,
RelationData relation, ref VirtualHPartitioningDefinition result)
{
if (attributePartitions.Count() > 0)
{
var first = attributePartitions.First();
foreach (var p in first.Partitions)
{
var pp = new List <RangeHPartitionAttributeDefinition>(partitionParts);
pp.Add(p);
GenerateRange(attributePartitions.Skip(1), pp, relation, ref result);
}
}
else
{
var toPart = partitionParts.Take(partitionParts.Count - 1).Select(x => toSqlValueStringConverter.ConvertStringRepresentation(x.DbType, x.FromValueInclusive)).ToList();
toPart.Add(partitionParts.Select(x => toSqlValueStringConverter.ConvertStringRepresentation(x.DbType, x.ToValueExclusive)).Last());
result.PartitionStatements.Add(String.Format("PARTITION OF {0}.{1} FOR VALUES FROM ({2}) TO ({3})",
relation.SchemaName, relation.Name,
String.Join(",", partitionParts.Select(x => toSqlValueStringConverter.ConvertStringRepresentation(x.DbType, x.FromValueInclusive))),
String.Join(",", toPart)
)
);
}
}
protected override void OnExecute()
{
using (var scope = new DatabaseScope(context.Database.Name))
{
virtualIndicesRepository.DestroyAll();
foreach (var index in context.IndicesDesignData.PossibleIndices.All)
{
Dictionary <AttributeData, List <string> > possibleFilteredAttributeValues = new Dictionary <AttributeData, List <string> >();
foreach (var a in index.Attributes)
{
List <string> mostSignificantValues = new List <string>();
List <string> leastSignificantValues = new List <string>();
if (a.MostCommonValuesFrequencies != null && a.MostCommonValuesFrequencies.Length >= 2)// we need at least two values
{
decimal frequenciesSum = 0;
for (int i = 0; i < Math.Min(a.MostCommonValuesFrequencies.Length - 1, MOST_COMMON_VALUES_MAX_COUNT); i++)
{
if (a.MostCommonValuesFrequencies[i] >= MOST_COMMON_VALUE_MIN_FREQUENCY)
{
var sqlStringValue = toSqlValueStringConverter.ConvertStringRepresentation(a.DbType, a.MostCommonValues[i]);
if (sqlStringValue != null)
{
mostSignificantValues.Add(sqlStringValue);
frequenciesSum += a.MostCommonValuesFrequencies[i];
}
}
}
if (frequenciesSum < MOST_COMMON_VALUES_MIN_FREQUENCIES_SUM || frequenciesSum > MOST_COMMON_VALUES_MAX_FREQUENCIES_SUM)
{
mostSignificantValues.Clear();
}
frequenciesSum = 0;
for (int i = a.MostCommonValuesFrequencies.Length - 1; i >= Math.Max(1, a.MostCommonValuesFrequencies.Length - MOST_COMMON_VALUES_MAX_COUNT + 1); i--)
{
var sqlStringValue = toSqlValueStringConverter.ConvertStringRepresentation(a.DbType, a.MostCommonValues[i]);
if (sqlStringValue != null)
{
leastSignificantValues.Add(sqlStringValue);
frequenciesSum += a.MostCommonValuesFrequencies[i];
}
}
if (frequenciesSum > MOST_COMMON_VALUES_MIN_FREQUENCIES_SUM)
{
leastSignificantValues.Clear();
}
}
if (mostSignificantValues.Count > 0)
{
possibleFilteredAttributeValues.Add(a, mostSignificantValues);
}
else if (leastSignificantValues.Count > 0)
{
possibleFilteredAttributeValues.Add(a, leastSignificantValues);
}
}
if (possibleFilteredAttributeValues.Count > 0)
{
string filter = CreateFilterString(possibleFilteredAttributeValues);
var targetRelationData = context.RelationsData.GetReplacementOrOriginal(index.Relation.ID);
var virtualIndex = virtualIndicesRepository.Create(dbObjectDefinitionGenerator.Generate(index.WithReplacedRelation(targetRelationData), filter));
var size = virtualIndicesRepository.GetVirtualIndexSize(virtualIndex.ID);
var filters = new Dictionary <string, long>();
filters.Add(filter, size);
context.IndicesDesignData.PossibleIndexFilters.Add(index, filters);
}
}
}
}