protected virtual Expression VisitProjection(DbProjectionExpression proj)
{
var select = this.Visit(proj.Select) as DbSelectExpression;
var projector = this.Visit(proj.Projector);
return(this.UpdateProjection(proj, select, projector, proj.Aggregator));
}
private Expression ExecuteProjection(DbProjectionExpression projection, bool okayToDefer, QueryCommand command, Expression[] values, bool isTopLevel)
{
okayToDefer &= this.receivingMember != null && this.policy.IsDeferLoaded(this.receivingMember);
var saveScope = this.scope;
var reader = Expression.Parameter(typeof(FieldReader), "r" + nReaders++);
this.scope = new Scope(this.scope, reader, projection.Select.Alias, projection.Select.Columns);
var projector = Expression.Lambda(this.Visit(projection.Projector), reader);
this.scope = saveScope;
var entity = EntityFinder.Find(projection.Projector);
var methExecute = okayToDefer ? nameof(QueryExecutor.ExecuteDeferred) : nameof(QueryExecutor.Execute);
var result = Expression.Call(this.executor, methExecute, new Type[] { projector.Body.Type }, Expression.Constant(command), projector, Expression.Constant(entity, typeof(MappingEntity)), Expression.NewArrayInit(typeof(object), values)) as Expression;
if (projection.Aggregator != null)
{
result = DbExpressionReplacer.Replace(projection.Aggregator.Body, projection.Aggregator.Parameters[0], result);
}
return(result);
}
protected override Expression VisitDeclaration(DbDeclarationCommand decl)
{
if (decl.Source != null)
{
var projection = new DbProjectionExpression
(
decl.Source,
Expression.NewArrayInit(typeof(object), decl.Variables.Select(v => v.Expression.Type.GetTypeInfo().IsValueType ? Expression.Convert(v.Expression, typeof(object)) : v.Expression).ToArray()),
DbAggregator.GetAggregator(typeof(object[]), typeof(IEnumerable <object[]>))
);
var vars = Expression.Parameter(typeof(object[]), "vars");
this.variables.Add(vars);
this.initializers.Add(Expression.Constant(null, typeof(object[])));
for (int i = 0, n = decl.Variables.Count; i < n; i++)
{
var v = decl.Variables[i];
var nv = new DbNamedValueExpression
(
v.Name, v.QueryType,
Expression.Convert(Expression.ArrayIndex(vars, Expression.Constant(i)), v.Expression.Type)
);
this.variableMap.Add(v.Name, nv);
}
return(MakeAssign(vars, this.Visit(projection)));
}
throw new InvalidOperationException("Declaration query not allowed for this langauge");
}
protected virtual bool CompareProjection(DbProjectionExpression a, DbProjectionExpression b)
{
if (!this.Compare(a.Select, b.Select))
{
return(false);
}
var save = this.aliasScope;
try
{
this.aliasScope = new ScopedDictionary <TableAlias, TableAlias>(this.aliasScope);
this.aliasScope.Add(a.Select.Alias, b.Select.Alias);
return
(
this.Compare(a.Projector, b.Projector) &&
this.Compare(a.Aggregator, b.Aggregator) &&
a.IsSingleton == b.IsSingleton
);
}
finally
{
this.aliasScope = save;
}
}
protected override Expression VisitProjection(DbProjectionExpression projection)
{
var projector = this.Visit(projection.Projector);
var select = this.Visit(projection.Select) as DbSelectExpression;
return(this.UpdateProjection(projection, select, projector, projection.Aggregator));
}
protected DbProjectionExpression UpdateProjection(DbProjectionExpression proj, DbSelectExpression select, Expression projector, LambdaExpression aggregator)
{
if (select != proj.Select || projector != proj.Projector || aggregator != proj.Aggregator)
{
return(new DbProjectionExpression(select, projector, aggregator));
}
return(proj);
}
public override Expression GetMemberExpression(Expression root, MappingEntity entity, MemberInfo member)
{
if (this.mapping.IsAssociationRelationship(entity, member))
{
var relatedEntity = this.mapping.GetRelatedEntity(entity, member);
var projection = this.GetQueryExpression(relatedEntity);
var declaredTypeMembers = this.mapping.GetAssociationKeyMembers(entity, member).ToList();
var associatedMembers = this.mapping.GetAssociationRelatedKeyMembers(entity, member).ToList();
var where = null as Expression;
for (int i = 0, n = associatedMembers.Count; i < n; i++)
{
var equal = this.GetMemberExpression
(
projection.Projector,
relatedEntity,
associatedMembers[i]).Equal(this.GetMemberExpression(root, entity, declaredTypeMembers[i])
);
where = (where != null) ? where.And(equal) : equal;
}
var newAlias = new TableAlias();
var pc = DbColumnProjector.ProjectColumns
(
this.translator.Linguist.Language,
projection.Projector, null,
newAlias,
projection.Select.Alias
);
var aggregator = DbAggregator.GetAggregator(TypeHelper.GetMemberType(member), typeof(IEnumerable <>).MakeGenericType(pc.Projector.Type));
var result = new DbProjectionExpression
(
new DbSelectExpression(newAlias, pc.Columns, projection.Select, where),
pc.Projector, aggregator
);
return(this.translator.Police.ApplyPolicy(result, member));
}
if (root is DbAliasedExpression aliasedRoot && this.mapping.IsColumn(entity, member))
{
return(new DbColumnExpression
(
TypeHelper.GetMemberType(member),
this.GetColumnType(entity, member),
aliasedRoot.Alias,
this.mapping.GetColumnName(entity, member)
));
}
return(DbQueryBinder.BindMember(root, member));
}
protected override Expression VisitProjection(DbProjectionExpression projection)
{
if (this.isTop)
{
this.isTop = false;
return(this.ExecuteProjection(projection, okayToDefer: this.scope != null, isTopLevel: true));
}
return(this.BuildInner(projection));
}
internal override DbProjectionExpression GetQueryExpression(MappingEntity entity)
{
var tableAlias = new TableAlias();
var selectAlias = new TableAlias();
var table = new DbTableExpression(tableAlias, entity, this.mapping.GetTableName(entity));
var projector = this.GetEntityExpression(table, entity) as Expression;
var pc = DbColumnProjector.ProjectColumns(this.translator.Linguist.Language, projector, null, selectAlias, tableAlias);
var proj = new DbProjectionExpression(new DbSelectExpression(selectAlias, pc.Columns, table, null), pc.Projector);
return(this.Translator.Police.ApplyPolicy(proj, entity.ElementType.GetTypeInfo()) as DbProjectionExpression);
}
protected override Expression VisitProjection(DbProjectionExpression proj)
{
if (isTopLevel)
{
isTopLevel = false;
this.currentSelect = proj.Select;
var projector = this.Visit(proj.Projector);
if (projector != proj.Projector || this.currentSelect != proj.Select)
{
return(new DbProjectionExpression(this.currentSelect, projector, proj.Aggregator));
}
return(proj);
}
if (proj.IsSingleton && this.CanJoinOnServer(this.currentSelect))
{
var newAlias = new TableAlias();
this.currentSelect = this.currentSelect.AddRedundantSelect(this.language, newAlias);
var source = DbColumnMapper.Map(proj.Select, newAlias, this.currentSelect.Alias) as DbSelectExpression;
var pex = this.language.AddOuterJoinTest(new DbProjectionExpression(source, proj.Projector));
var pc = DbColumnProjector.ProjectColumns(this.language, pex.Projector, this.currentSelect.Columns, this.currentSelect.Alias, newAlias, proj.Select.Alias);
var join = new DbJoinExpression(JoinType.OuterApply, this.currentSelect.From, pex.Select, null);
this.currentSelect = new DbSelectExpression(this.currentSelect.Alias, pc.Columns, join, null);
return(this.Visit(pc.Projector));
}
var saveTop = this.isTopLevel;
var saveSelect = this.currentSelect;
this.isTopLevel = true;
this.currentSelect = null;
var result = base.VisitProjection(proj);
this.isTopLevel = saveTop;
this.currentSelect = saveSelect;
return(result);
}
public static DbProjectionExpression AddOuterJoinTest(this DbProjectionExpression proj, QueryLanguage language, Expression expression)
{
var colName = proj.Select.Columns.GetAvailableColumnName("Test");
var colType = language.TypeSystem.GetColumnType(expression.Type);
var newSource = proj.Select.AddColumn(new DbColumnDeclaration(colName, expression, colType));
var newProjector = new DbOuterJoinedExpression
(
new DbColumnExpression(expression.Type, colType, newSource.Alias, colName),
proj.Projector
);
return(new DbProjectionExpression(newSource, newProjector, proj.Aggregator));
}
private Expression ExecuteProjection(DbProjectionExpression projection, bool okayToDefer, bool isTopLevel)
{
projection = this.Parameterize(projection) as DbProjectionExpression;
if (this.scope != null)
{
projection = OuterParameterizer.Parameterize(this.scope.Alias, projection) as DbProjectionExpression;
}
var commandText = this.linguist.Format(projection.Select);
var namedValues = DbNamedValueGatherer.Gather(projection.Select);
var command = new QueryCommand(commandText, namedValues.Select(v => new QueryParameter(v.Name, v.Type, v.QueryType)));
var values = namedValues.Select(v => Expression.Convert(this.Visit(v.Value), typeof(object))).ToArray() as Expression[];
return(this.ExecuteProjection(projection, okayToDefer, command, values, isTopLevel));
}
protected override Expression VisitProjection(DbProjectionExpression proj)
{
proj = base.VisitProjection(proj) as DbProjectionExpression;
if (proj.Select.From is DbSelectExpression)
{
var redundant = RedundantSubqueryGatherer.Gather(proj.Select);
if (redundant != null)
{
proj = DbSubqueryRemover.Remove(proj, redundant);
}
}
return(proj);
}
protected override Expression VisitProjection(DbProjectionExpression proj)
{
if ((proj.Projector is DbColumnExpression) || this.ForDebug)
{
this.Write("(");
this.WriteLine(Indentation.Inner);
this.Visit(proj.Select);
this.Write(")");
this.Indent(Indentation.Outer);
}
else
{
throw new NotSupportedException("Non-scalar projections cannot be translated to SQL.");
}
return(proj);
}
protected override Expression VisitExists(DbExistsExpression exists)
{
var colType = this.linguist.Language.TypeSystem.GetColumnType(typeof(int));
var newSelect = exists.Select.SetColumns(new[]
{
new DbColumnDeclaration("value", new DbAggregateExpression(typeof(int), "Count", null, false), colType)
});
var projection = new DbProjectionExpression
(
newSelect,
new DbColumnExpression(typeof(int), colType, newSelect.Alias, "value"),
DbAggregator.GetAggregator(typeof(int), typeof(IEnumerable <int>))
);
return(this.Visit(projection.GreaterThan(Expression.Constant(0))));
}
protected virtual Expression VisitProjection(DbProjectionExpression projection)
{
this.AddAlias(projection.Select.Alias);
this.Write("Project(");
this.WriteLine(Indentation.Inner);
this.Write("@\"");
this.Visit(projection.Select);
this.Write("\",");
this.WriteLine(Indentation.Same);
this.Visit(projection.Projector);
this.Write(",");
this.WriteLine(Indentation.Same);
this.Visit(projection.Aggregator);
this.WriteLine(Indentation.Outer);
this.Write(")");
return(projection);
}
internal virtual DbProjectionExpression AddOuterJoinTest(DbProjectionExpression proj)
{
var test = this.GetOuterJoinTest(proj.Select);
var select = proj.Select;
var testCol = null as DbColumnExpression;
foreach (var col in select.Columns)
{
if (test.Equals(col.Expression))
{
testCol = new DbColumnExpression(test.Type, TypeSystem.GetColumnType(test.Type), select.Alias, col.Name);
break;
}
}
if (testCol == null)
{
testCol = test as DbColumnExpression;
var colName = testCol != null ? testCol.Name : "Test";
if (colName != null)
{
colName = proj.Select.Columns.GetAvailableColumnName(colName);
}
var colType = this.TypeSystem.GetColumnType(test.Type);
if (colType != null)
{
select = select.AddColumn(new DbColumnDeclaration(colName, test, colType));
testCol = new DbColumnExpression(test.Type, colType, select.Alias, colName);
}
}
return(new DbProjectionExpression
(
select,
new DbOuterJoinedExpression(testCol, proj.Projector),
proj.Aggregator
));
}
protected override Expression VisitClientJoin(DbClientJoinExpression join)
{
var innerKey = MakeJoinKey(join.InnerKey);
var outerKey = MakeJoinKey(join.OuterKey);
var kvpConstructor = typeof(KeyValuePair <,>).MakeGenericType(innerKey.Type, join.Projection.Projector.Type).GetConstructor(new Type[] { innerKey.Type, join.Projection.Projector.Type });
var constructKVPair = Expression.New(kvpConstructor, innerKey, join.Projection.Projector);
var newProjection = new DbProjectionExpression(join.Projection.Select, constructKVPair);
var iLookup = ++nLookup;
var execution = this.ExecuteProjection(newProjection, okayToDefer: false, isTopLevel: false);
var kvp = Expression.Parameter(constructKVPair.Type, "kvp");
if (join.Projection.Projector.NodeType == (ExpressionType)DbExpressionType.OuterJoined)
{
var pred = Expression.Lambda
(
Expression.PropertyOrField(kvp, "Value").NotEqual(TypeHelper.GetNullConstant(join.Projection.Projector.Type)),
kvp
);
execution = Expression.Call(typeof(Enumerable), nameof(Enumerable.Where), new Type[] { kvp.Type }, execution, pred);
}
var keySelector = Expression.Lambda(Expression.PropertyOrField(kvp, "Key"), kvp);
var elementSelector = Expression.Lambda(Expression.PropertyOrField(kvp, "Value"), kvp);
var toLookup = Expression.Call(typeof(Enumerable), nameof(Enumerable.ToLookup), new Type[] { kvp.Type, outerKey.Type, join.Projection.Projector.Type }, execution, keySelector, elementSelector);
var lookup = Expression.Parameter(toLookup.Type, "lookup" + iLookup);
var property = lookup.Type.GetProperty("Item");
var access = Expression.Call(lookup, property.GetGetMethod(), this.Visit(outerKey)) as Expression;
if (join.Projection.Aggregator != null)
{
access = DbExpressionReplacer.Replace(join.Projection.Aggregator.Body, join.Projection.Aggregator.Parameters[0], access);
}
this.variables.Add(lookup);
this.initializers.Add(toLookup);
return(access);
}
internal override DbProjectionExpression GetQueryExpression(MappingEntity entity)
{
var tables = this.mapping.GetTables(entity);
if (tables.Count <= 1)
{
return(base.GetQueryExpression(entity));
}
var aliases = new Dictionary <string, TableAlias>();
var rootTable = tables.Single(ta => !this.mapping.IsExtensionTable(ta));
var tex = new DbTableExpression(new TableAlias(), entity, this.mapping.GetTableName(rootTable));
aliases.Add(this.mapping.GetAlias(rootTable), tex.Alias);
var source = tex as Expression;
foreach (var table in tables.Where(t => this.mapping.IsExtensionTable(t)))
{
var joinedTableAlias = new TableAlias();
var extensionAlias = this.mapping.GetAlias(table);
aliases.Add(extensionAlias, joinedTableAlias);
var keyColumns = this.mapping.GetExtensionKeyColumnNames(table).ToList();
var relatedMembers = this.mapping.GetExtensionRelatedMembers(table).ToList();
var relatedAlias = this.mapping.GetExtensionRelatedAlias(table);
aliases.TryGetValue(relatedAlias, out TableAlias relatedTableAlias);
var joinedTex = new DbTableExpression(joinedTableAlias, entity, this.mapping.GetTableName(table));
var cond = null as Expression;
for (int i = 0, n = keyColumns.Count; i < n; i++)
{
var memberType = TypeHelper.GetMemberType(relatedMembers[i]);
var colType = this.GetColumnType(entity, relatedMembers[i]);
var relatedColumn = new DbColumnExpression(memberType, colType, relatedTableAlias, this.mapping.GetColumnName(entity, relatedMembers[i]));
var joinedColumn = new DbColumnExpression(memberType, colType, joinedTableAlias, keyColumns[i]);
var eq = joinedColumn.Equal(relatedColumn);
cond = (cond != null) ? cond.And(eq) : eq;
}
source = new DbJoinExpression(JoinType.SingletonLeftOuter, source, joinedTex, cond);
}
var columns = new List <DbColumnDeclaration>();
this.GetColumns(entity, aliases, columns);
var root = new DbSelectExpression(new TableAlias(), columns, source, null);
var existingAliases = aliases.Values.ToArray();
var projector = this.GetEntityExpression(root, entity) as Expression;
var selectAlias = new TableAlias();
var pc = DbColumnProjector.ProjectColumns(this.Translator.Linguist.Language, projector, null, selectAlias, root.Alias);
var proj = new DbProjectionExpression
(
new DbSelectExpression(selectAlias, pc.Columns, root, null),
pc.Projector
);
return(this.Translator.Police.ApplyPolicy(proj, entity.ElementType.GetTypeInfo()) as DbProjectionExpression);
}
public static DbProjectionExpression Remove(DbProjectionExpression projection, params DbSelectExpression[] selectsToRemove)
{
return(Remove(projection, selectsToRemove as IEnumerable <DbSelectExpression>));
}
public static DbProjectionExpression Remove(DbProjectionExpression projection, IEnumerable <DbSelectExpression> selectsToRemove)
{
return(new DbSubqueryRemover(selectsToRemove).Visit(projection) as DbProjectionExpression);
}
protected override Expression VisitProjection(DbProjectionExpression proj)
{
var save = this.currentSelect;
this.currentSelect = proj.Select;
try
{
if (this.isTopLevel == false)
{
if (this.CanJoinOnClient(this.currentSelect))
{
var newOuterSelect = DbQueryDuplicator.Duplicate(save) as DbSelectExpression;
var newInnerSelect = DbColumnMapper.Map(proj.Select, newOuterSelect.Alias, save.Alias) as DbSelectExpression;
var newInnerProjection = this.language.AddOuterJoinTest(new DbProjectionExpression(newInnerSelect, proj.Projector));
if (newInnerProjection != null)
{
newInnerSelect = newInnerProjection.Select;
}
var newProjector = newInnerProjection.Projector;
var newAlias = new TableAlias();
var pc = DbColumnProjector.ProjectColumns(this.language, newProjector, null, newAlias, newOuterSelect.Alias, newInnerSelect.Alias);
var join = new DbJoinExpression(JoinType.OuterApply, newOuterSelect, newInnerSelect, null);
var joinedSelect = new DbSelectExpression(newAlias, pc.Columns, join, null, null, null, proj.IsSingleton, null, null, false);
this.currentSelect = joinedSelect;
if (pc != null)
{
newProjector = this.Visit(pc.Projector);
}
var outerKeys = new List <Expression>();
var innerKeys = new List <Expression>();
if (this.GetEquiJoinKeyExpressions(newInnerSelect.Where, newOuterSelect.Alias, outerKeys, innerKeys))
{
var outerKey = outerKeys.Select(k => DbColumnMapper.Map(k, save.Alias, newOuterSelect.Alias));
var innerKey = innerKeys.Select(k => DbColumnMapper.Map(k, joinedSelect.Alias, ((DbColumnExpression)k).Alias));
var newProjection = new DbProjectionExpression(joinedSelect, newProjector, proj.Aggregator);
return(new DbClientJoinExpression(newProjection, outerKey, innerKey));
}
}
else
{
var saveJoin = this.canJoinOnClient;
this.canJoinOnClient = false;
var result = base.VisitProjection(proj);
this.canJoinOnClient = saveJoin;
return(result);
}
}
else
{
this.isTopLevel = false;
}
return(base.VisitProjection(proj));
}
finally
{
this.currentSelect = save;
}
}
protected DbClientJoinExpression UpdateClientJoin(DbClientJoinExpression join, DbProjectionExpression projection, IEnumerable <Expression> outerKey, IEnumerable <Expression> innerKey)
{
if (projection != join.Projection || outerKey != join.OuterKey || innerKey != join.InnerKey)
{
return(new DbClientJoinExpression(projection, outerKey, innerKey));
}
return(join);
}
protected virtual Expression GetInsertResult(MappingEntity entity, Expression instance, LambdaExpression selector, Dictionary <MemberInfo, Expression> map)
{
var tableAlias = new TableAlias();
var tex = new DbTableExpression(tableAlias, entity, this.mapping.GetTableName(entity));
var aggregator = DbAggregator.GetAggregator(selector.Body.Type, typeof(IEnumerable <>).MakeGenericType(selector.Body.Type));
var where = null as Expression;
var genIdCommand = null as DbDeclarationCommand;
var generatedIds = this.mapping.GetMappedMembers(entity).Where(m => this.mapping.IsPrimaryKey(entity, m) && this.mapping.IsGenerated(entity, m)).ToList();
if (generatedIds.Count > 0)
{
if (map == null || !generatedIds.Any(m => map.ContainsKey(m)))
{
var localMap = new Dictionary <MemberInfo, Expression>();
genIdCommand = this.GetGeneratedIdCommand(entity, generatedIds.ToList(), localMap);
map = localMap;
}
if (selector.Body is MemberExpression mex && this.mapping.IsPrimaryKey(entity, mex.Member) && this.mapping.IsGenerated(entity, mex.Member))
{
if (genIdCommand != null)
{
return(new DbProjectionExpression
(
genIdCommand.Source,
new DbColumnExpression(mex.Type, genIdCommand.Variables[0].QueryType, genIdCommand.Source.Alias, genIdCommand.Source.Columns[0].Name),
aggregator
));
}
else
{
var alias = new TableAlias();
var colType = this.GetColumnType(entity, mex.Member);
return(new DbProjectionExpression
(
new DbSelectExpression(alias, new[] { new DbColumnDeclaration(string.Empty, map[mex.Member], colType) }, null, null),
new DbColumnExpression(TypeHelper.GetMemberType(mex.Member), colType, alias, string.Empty),
aggregator
));
}
}
where = generatedIds.Select((m, i) => this.GetMemberExpression(tex, entity, m).Equal(map[m])).Aggregate((x, y) => x.And(y));
}
else
{
where = this.GetIdentityCheck(tex, entity, instance);
}
var typeProjector = this.GetEntityExpression(tex, entity);
var selection = DbExpressionReplacer.Replace(selector.Body, selector.Parameters[0], typeProjector);
var newAlias = new TableAlias();
var pc = DbColumnProjector.ProjectColumns(this.translator.Linguist.Language, selection, null, newAlias, tableAlias);
var pe = new DbProjectionExpression
(
new DbSelectExpression(newAlias, pc.Columns, tex, where),
pc.Projector,
aggregator
);
if (genIdCommand != null)
{
return(new DbBlockCommand(genIdCommand, pe));
}
return(pe);
}
protected override Expression VisitProjection(DbProjectionExpression proj)
{
return(this.UpdateProjection(proj, proj.Select, this.Visit(proj.Projector), proj.Aggregator));
}
protected override Expression VisitProjection(DbProjectionExpression proj)
{
this.Visit(proj.Projector);
return(proj);
}
public DbClientJoinExpression(DbProjectionExpression projection, IEnumerable <Expression> outerKey, IEnumerable <Expression> innerKey) : base(DbExpressionType.ClientJoin, projection.Type)
{
this.OuterKey = outerKey.ToReadOnly();
this.InnerKey = innerKey.ToReadOnly();
this.Projection = projection;
}