| public AddPlan ( IQueryPlanNode plan, IFromTableSource tableSource ) : void | ||
| plan | IQueryPlanNode | |
| tableSource | IFromTableSource | |
| return | void | |
private QueryTablePlanner CreateTablePlanner(IRequest context, QueryExpressionFrom queryFrom)
{
// Set up plans for each table in the from clause of the command. For
// sub-queries, we recurse.
var tablePlanner = new QueryTablePlanner();
for (int i = 0; i < queryFrom.SourceCount; i++)
{
var tableSource = queryFrom.GetTableSource(i);
IQueryPlanNode plan;
if (tableSource is FromTableSubQuerySource)
{
var subQuerySource = (FromTableSubQuerySource)tableSource;
var subQueryExpr = subQuerySource.QueryExpression;
var subQueryFrom = subQuerySource.QueryFrom;
plan = PlanQuery(context, subQueryExpr, subQueryFrom, null, null);
if (!(plan is SubsetNode))
{
throw new InvalidOperationException("The root node of a sub-query plan must be a subset.");
}
var subsetNode = (SubsetNode)plan;
subsetNode.SetAliasParentName(subQuerySource.AliasName);
}
else if (tableSource is FromTableDirectSource)
{
var directSource = (FromTableDirectSource)tableSource;
plan = directSource.QueryPlan;
}
else
{
throw new InvalidOperationException(String.Format("The type of FROM source '{0}' is not supported.", tableSource.GetType()));
}
tablePlanner.AddPlan(plan, tableSource);
}
return(tablePlanner);
}
private QueryTablePlanner CreateTablePlanner(IQueryContext context, QueryExpressionFrom queryFrom)
{
// Set up plans for each table in the from clause of the command. For
// sub-queries, we recurse.
var tablePlanner = new QueryTablePlanner();
for (int i = 0; i < queryFrom.SourceCount; i++) {
var tableSource = queryFrom.GetTableSource(i);
IQueryPlanNode plan;
if (tableSource is FromTableSubQuerySource) {
var subQuerySource = (FromTableSubQuerySource) tableSource;
var subQueryExpr = subQuerySource.QueryExpression;
var subQueryFrom = subQuerySource.QueryFrom;
plan = PlanQuery(context, subQueryExpr, subQueryFrom, null);
if (!(plan is SubsetNode))
throw new InvalidOperationException("The root node of a sub-query plan must be a subset.");
var subsetNode = (SubsetNode) plan;
subsetNode.SetAliasParentName(subQuerySource.AliasName);
} else if (tableSource is FromTableDirectSource) {
var directSource = (FromTableDirectSource) tableSource;
plan = directSource.QueryPlan;
} else {
throw new InvalidOperationException(String.Format("The type of FROM source '{0}' is not supported.", tableSource.GetType()));
}
tablePlanner.AddPlan(plan, tableSource);
}
return tablePlanner;
}
private TablePlan NaturallyJoinPlans(TablePlan plan1, TablePlan plan2)
{
JoinType joinType;
SqlExpression onExpr;
TablePlan leftPlan, rightPlan;
// Are the plans linked by common join information?
if (plan1.RightPlan == plan2) {
joinType = plan1.RightJoinType;
onExpr = plan1.RightOnExpression;
leftPlan = plan1;
rightPlan = plan2;
} else if (plan1.LeftPlan == plan2) {
joinType = plan1.LeftJoinType;
onExpr = plan1.LeftOnExpression;
leftPlan = plan2;
rightPlan = plan1;
} else {
// Assertion - make sure no join clashes!
if ((plan1.LeftPlan != null && plan2.LeftPlan != null) ||
(plan1.RightPlan != null && plan2.RightPlan != null)) {
throw new InvalidOperationException("Plans can not be naturally join because " +
"the left/right join plans clash.");
}
// Else we must assume a non-dependent join (not an outer join).
// Perform a natural join
IQueryPlanNode node1 = new NaturalJoinNode(plan1.Plan, plan2.Plan);
return MergePlans(plan1, plan2, node1);
}
// This means plan1 and plan2 are linked by a common join and ON
// expression which we evaluate now.
bool outerJoin;
if (joinType == JoinType.Left) {
// Mark the left plan
leftPlan.UpdatePlan(new MarkerNode(leftPlan.Plan, "OUTER_JOIN"));
outerJoin = true;
} else if (joinType == JoinType.Right) {
// Mark the right plan
rightPlan.UpdatePlan(new MarkerNode(rightPlan.Plan, "OUTER_JOIN"));
outerJoin = true;
} else if (joinType == JoinType.Inner) {
// Inner join with ON expression
outerJoin = false;
} else {
throw new InvalidOperationException(String.Format("Join type ({0}) is not supported.", joinType));
}
// Make a Planner object for joining these plans.
var planner = new QueryTablePlanner();
planner.AddPlan(leftPlan.Clone());
planner.AddPlan(rightPlan.Clone());
// Evaluate the on expression
var node = planner.LogicalEvaluate(onExpr);
// If outer join add the left outer join node
if (outerJoin)
node = new LeftOuterJoinNode(node, "OUTER_JOIN");
// And merge the plans in this set with the new node.
return MergePlans(plan1, plan2, node);
}
private TablePlan NaturallyJoinPlans(TablePlan plan1, TablePlan plan2)
{
JoinType joinType;
SqlExpression onExpr;
TablePlan leftPlan, rightPlan;
// Are the plans linked by common join information?
if (plan1.RightPlan == plan2)
{
joinType = plan1.RightJoinType;
onExpr = plan1.RightOnExpression;
leftPlan = plan1;
rightPlan = plan2;
}
else if (plan1.LeftPlan == plan2)
{
joinType = plan1.LeftJoinType;
onExpr = plan1.LeftOnExpression;
leftPlan = plan2;
rightPlan = plan1;
}
else
{
// Assertion - make sure no join clashes!
if ((plan1.LeftPlan != null && plan2.LeftPlan != null) ||
(plan1.RightPlan != null && plan2.RightPlan != null))
{
throw new InvalidOperationException("Plans can not be naturally join because " +
"the left/right join plans clash.");
}
// Else we must assume a non-dependent join (not an outer join).
// Perform a natural join
var node1 = new NaturalJoinNode(plan1.Plan, plan2.Plan);
return(MergePlans(plan1, plan2, node1));
}
// This means plan1 and plan2 are linked by a common join and ON
// expression which we evaluate now.
bool outerJoin;
if (joinType == JoinType.Left)
{
// Mark the left plan
leftPlan.UpdatePlan(new MarkerNode(leftPlan.Plan, "OUTER_JOIN"));
outerJoin = true;
}
else if (joinType == JoinType.Right)
{
// Mark the right plan
rightPlan.UpdatePlan(new MarkerNode(rightPlan.Plan, "OUTER_JOIN"));
outerJoin = true;
}
else if (joinType == JoinType.Inner)
{
// Inner join with ON expression
outerJoin = false;
}
else
{
throw new InvalidOperationException(String.Format("Join type ({0}) is not supported.", joinType));
}
// Make a Planner object for joining these plans.
var planner = new QueryTablePlanner();
planner.AddPlan(leftPlan.Clone());
planner.AddPlan(rightPlan.Clone());
// Evaluate the on expression
var node = planner.LogicalEvaluate(onExpr);
// If outer join add the left outer join node
if (outerJoin)
{
node = new LeftOuterJoinNode(node, "OUTER_JOIN");
}
// And merge the plans in this set with the new node.
return(MergePlans(plan1, plan2, node));
}
