pack-priv abstract Class TableOperatorNode

Overrides org.apache.derby.impl.sql.compile.FromTable.acceptChildren.

Accept the visitor for all visitable children of this node.

Parameters

v:Visitor

the visitor

Annotations

@Override

Exceptions

StandardException:

on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.adjustForSortElimination.

Doc from org.apache.derby.impl.sql.compile.ResultSetNode.adjustForSortElimination.

Notify the underlying result set tree that the optimizer has chosen to "eliminate" a sort. Sort elimination can happen as part of preprocessing (see esp. SelectNode.preprocess(...)) or it can happen if the optimizer chooses an access path that inherently returns the rows in the correct order (also known as a "sort avoidance" plan). In either case we drop the sort and rely on the underlying result set tree to return its rows in the correct order. For most types of ResultSetNodes we automatically get the rows in the correct order if the sort was eliminated. One exception to this rule, though, is the case of an IndexRowToBaseRowNode, for which we have to disable bulk fetching on the underlying base table. Otherwise the index scan could return rows out of order if the base table is updated while the scan is "in progress" (i.e. while the result set is open). In order to account for this (and potentially other, similar issues in the future) this method exists to notify the result set node that it is expected to return rows in the correct order. The result set can then take necessary action to satsify this requirement--such as disabling bulk fetch in the case of IndexRowToBaseRowNode. All of that said, any ResultSetNodes for which we could potentially eliminate sorts should override this method accordingly. So we don't ever expect to get here.

Annotations

@Override

See Also

ResultSetNode#adjustForSortElimination

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.adjustForSortElimination.

Doc from org.apache.derby.impl.sql.compile.ResultSetNode.adjustForSortElimination.

Same goal as adjustForSortElimination above, but this version takes a RequiredRowOrdering to allow nodes to adjust based on the ORDER BY clause, if needed.

Annotations

@Override

See Also

ResultSetNode#adjustForSortElimination

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindExpressions.

Bind the expressions under this TableOperatorNode. This means binding the sub-expressions, as well as figuring out what the return type is for each expression.

Parameters

fromListParam:FromList

Doc from org.apache.derby.impl.sql.compile.ResultSetNode.bindExpressions.

FromList to use/append to.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindExpressionsWithTables.

Bind the expressions in this ResultSetNode if it has tables. This means binding the sub-expressions, as well as figuring out what the return type is for each expression.

Parameters

fromListParam:FromList

FromList to use/append to.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindNonVTITables.

Bind the non VTI tables in this TableOperatorNode. This means getting their TableDescriptors from the DataDictionary. We will build an unbound RCL for this node. This RCL must be "bound by hand" after the underlying left and right RCLs are bound.

Parameters

dataDictionary:DataDictionary

The DataDictionary to use for binding

fromListParam:FromList

FromList to use/append to.

Returns:ResultSetNode

ResultSetNode Returns this.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindResultColumns.

Bind the result columns of this ResultSetNode when there is no base table to bind them to. This is useful for SELECT statements, where the result columns get their types from the expressions that live under them.

Parameters

fromListParam:FromList

FromList to use/append to.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindResultColumns.

Bind the result columns for this ResultSetNode to a base table. This is useful for INSERT and UPDATE statements, where the result columns get their types from the table being updated or inserted into. If a result column list is specified, then the verification that the result column list does not contain any duplicates will be done when binding them by name.

Parameters

targetTableDescriptor:TableDescriptor

The TableDescriptor for the table being updated or inserted into

targetColumnList:ResultColumnList

For INSERT statements, the user does not have to supply column names (for example, "insert into t values (1,2,3)". When this parameter is null, it means that the user did not supply column names, and so the binding should be done based on order. When it is not null, it means do the binding by name, not position.

statement:DMLStatementNode

Calling DMLStatementNode (Insert or Update)

fromListParam:FromList

FromList to use/append to.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindUntypedNullsToResultColumns.

DERBY-4365 Bind untyped nulls to the types in the given ResultColumnList. This is used for binding the nulls in row constructors and table constructors.

Parameters

rcl:ResultColumnList

The ResultColumnList with the types to bind nulls to

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.bindVTITables.

Bind the VTI tables in this TableOperatorNode. This means getting their TableDescriptors from the DataDictionary. We will build an unbound RCL for this node. This RCL must be "bound by hand" after the underlying left and right RCLs are bound.

Parameters

fromListParam:FromList

FromList to use/append to.

Returns:ResultSetNode

ResultSetNode Returns this.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.FromTable.decrementLevel.

Decrement (query block) level (0-based) for all of the tables in this ResultSet tree. This is useful when flattening a subquery.

Parameters

decrement:int

The amount to decrement by.

Annotations

@Override

Overrides org.apache.derby.impl.sql.compile.FromTable.getExposedName.

Return the exposed name for this table, which is the name that can be used to refer to this table in the rest of the query.

Returns:String

The exposed name for this table.

Annotations

@Override

Overrides org.apache.derby.impl.sql.compile.FromTable.getFromTableByName.

Determine whether or not the specified name is an exposed name in the current query block.

Parameters

name:String

The specified name to search for as an exposed name.

schemaName:String

Schema name, if non-null.

exactMatch:boolean

Whether or not we need an exact match on specified schema and table names or match on table id.

Returns:FromTable

The FromTable, if any, with the exposed name.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Get the leftResultSet from this node.

Returns:ResultSetNode

ResultSetNode The leftResultSet from this node.

Get the rightResultSet from this node.

Returns:ResultSetNode

ResultSetNode The rightResultSet from this node.

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.modifyAccessPaths.

Doc from org.apache.derby.impl.sql.compile.ResultSetNode.modifyAccessPaths.

Modify the access paths according to the decisions the optimizer made. This can include adding project/restrict nodes, index-to-base-row nodes, etc.

Returns:ResultSetNode

The modified query tree

Annotations

@Override

Exceptions

StandardException:

Thrown on error

See Also

ResultSetNode#modifyAccessPaths

Overrides org.apache.derby.impl.sql.compile.FromTable.needsSpecialRCLBinding.

apparently something special needs to be done for me....

Annotations

@Override

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.optimize.

Optimize a TableOperatorNode.

Parameters

dataDictionary:DataDictionary

The DataDictionary to use for optimization

predicateList:PredicateList

The PredicateList to apply.

outerRows:double

Doc from org.apache.derby.impl.sql.compile.ResultSetNode.optimize.

The number of outer joining rows

Returns:ResultSetNode

ResultSetNode The top of the optimized query tree

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.preprocess.

Put a ProjectRestrictNode on top of each FromTable in the FromList. ColumnReferences must continue to point to the same ResultColumn, so that ResultColumn must percolate up to the new PRN. However, that ResultColumn will point to a new expression, a VirtualColumnNode, which points to the FromTable and the ResultColumn that is the source for the ColumnReference. (The new PRN will have the original of the ResultColumnList and the ResultColumns from that list. The FromTable will get shallow copies of the ResultColumnList and its ResultColumns. ResultColumn.expression will remain at the FromTable, with the PRN getting a new VirtualColumnNode for each ResultColumn.expression.) We then project out the non-referenced columns. If there are no referenced columns, then the PRN's ResultColumnList will consist of a single ResultColumn whose expression is 1.

Parameters

numTables:int

Number of tables in the DML Statement

gbl:GroupByList

The group by list, if any

fromList:FromList

The from list, if any

Returns:ResultSetNode

The generated ProjectRestrictNode atop the original FromTable.

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.printSubNodes.

Prints the sub-nodes of this object. See QueryTreeNode.java for how tree printing is supposed to work.

Parameters

depth:int

The depth of this node in the tree

Annotations

@Override

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.projectResultColumns.

Find the unreferenced result columns and project them out. This is used in pre-processing joins that are not flattened into the where clause.

Annotations

@Override

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.referencesTarget.

Search to see if a query references the specifed table name.

Parameters

name:String

Table name (String) to search for.

baseTable:boolean

Whether or not name is for a base table

Returns:boolean

true if found, else false

Annotations

@Override

Exceptions

StandardException:

Thrown on error

Overrides org.apache.derby.impl.sql.compile.ResultSetNode.rejectParameters.

Check for (and reject) ? parameters directly under the ResultColumns. This is done for SELECT statements. For TableOperatorNodes, we simply pass the check through to the left and right children.

Annotations

@Override

Exceptions

StandardException:

Thrown if a ? parameter found directly under a ResultColumn

Overrides org.apache.derby.impl.sql.compile.FromTable.setLevel.

Set the (query block) level (0-based) for this FromTable.

Parameters

level:int

The query block level for this FromTable.

Annotations

@Override

Mark whether or not this node is nested in parens. (Useful to parser since some trees get created left deep and others right deep.) The resulting state of this cal was never used so its field was removed to save runtimespace for this node. Further cleanup can be done including parser changes if this call is really nor required.

Parameters

nestedInParens:boolean

Whether or not this node is nested in parens.

Set the referenced columns in the column list if it may not be correct.