Class BinaryOperatorNode

java.lang.Object
org.apache.derby.impl.sql.compile.QueryTreeNode
org.apache.derby.impl.sql.compile.ValueNode
org.apache.derby.impl.sql.compile.OperatorNode
org.apache.derby.impl.sql.compile.BinaryOperatorNode
All Implemented Interfaces:
Visitable
Direct Known Subclasses:
BinaryArithmeticOperatorNode, BinaryComparisonOperatorNode, BinaryLogicalOperatorNode, ConcatenationOperatorNode, TimestampOperatorNode
class BinaryOperatorNode extends OperatorNode
A BinaryOperatorNode represents a built-in binary operator as defined by the ANSI/ISO SQL standard. This covers operators like +, -, *, /, =, <, etc. Java operators are not represented here: the JSQL language allows Java methods to be called from expressions, but not Java operators.

  • Field Details

  • Constructor Details

  • Method Details

    • toString

      public String toString()
      Convert this object to a String. See comments in QueryTreeNode.java for how this should be done for tree printing.
      Overrides:
      toString in class ValueNode
      Returns:
      This object as a String

    • setOperator

      void setOperator(String operator)
      Set the operator.
      Parameters:
      operator - The operator.

    • setMethodName

      void setMethodName(String methodName)
      Set the methodName.
      Parameters:
      methodName - The methodName.

    • setLeftRightInterfaceType

      void setLeftRightInterfaceType(String iType)
      Set the interface type for the left and right arguments. Used when we don't know the interface type until later in binding.

    • printSubNodes

      void printSubNodes(int depth)
      Prints the sub-nodes of this object. See QueryTreeNode.java for how tree printing is supposed to work.
      Overrides:
      printSubNodes in class QueryTreeNode
      Parameters:
      depth - The depth of this node in the tree

    • bindExpression

      ValueNode bindExpression(FromList fromList, SubqueryList subqueryList, List<AggregateNode> aggregates) throws StandardException
      Bind this expression. This means binding the sub-expressions, as well as figuring out what the return type is for this expression.
      Overrides:
      bindExpression in class ValueNode
      Parameters:
      fromList - The FROM list for the query this expression is in, for binding columns.
      subqueryList - The subquery list being built as we find SubqueryNodes
      aggregates - The aggregate list being built as we find AggregateNodes
      Returns:
      The new top of the expression tree.
      Throws:
      StandardException - Thrown on error

    • bindXMLQuery

      public ValueNode bindXMLQuery() throws StandardException
      Bind an XMLEXISTS or XMLQUERY operator. Makes sure the operand type and target type are both correct and sets the result type.
      Throws:
      StandardException - Thrown on error

    • genSQLJavaSQLTree

      ValueNode genSQLJavaSQLTree() throws StandardException
      generate a SQL->Java->SQL conversion tree above the left and right operand of this Binary Operator Node if needed. Subclasses can override the default behavior.
      Overrides:
      genSQLJavaSQLTree in class ValueNode
      Returns:
      ValueNode The new tree.
      Throws:
      StandardException - Thrown on error

    • preprocess

      ValueNode preprocess(int numTables, FromList outerFromList, SubqueryList outerSubqueryList, PredicateList outerPredicateList) throws StandardException
      Preprocess an expression tree. We do a number of transformations here (including subqueries, IN lists, LIKE and BETWEEN) plus subquery flattening. NOTE: This is done before the outer ResultSetNode is preprocessed.
      Overrides:
      preprocess in class ValueNode
      Parameters:
      numTables - Number of tables in the DML Statement
      outerFromList - FromList from outer query block
      outerSubqueryList - SubqueryList from outer query block
      outerPredicateList - PredicateList from outer query block
      Returns:
      The modified expression
      Throws:
      StandardException - Thrown on error

    • generateExpression

      void generateExpression(ExpressionClassBuilder acb, MethodBuilder mb) throws StandardException
      Do code generation for this binary operator.
      Overrides:
      generateExpression in class ValueNode
      Parameters:
      acb - The ExpressionClassBuilder for the class we're generating
      mb - The method the code to place the code
      Throws:
      StandardException - Thrown on error

    • setLeftOperand

      void setLeftOperand(ValueNode newLeftOperand)
      Set the leftOperand to the specified ValueNode
      Parameters:
      newLeftOperand - The new leftOperand

    • getLeftOperand

      ValueNode getLeftOperand()
      Get the leftOperand
      Returns:
      The current leftOperand.

    • setRightOperand

      void setRightOperand(ValueNode newRightOperand)
      Set the rightOperand to the specified ValueNode
      Parameters:
      newRightOperand - The new rightOperand

    • getRightOperand

      ValueNode getRightOperand()
      Get the rightOperand
      Returns:
      The current rightOperand.

    • categorize

      boolean categorize(JBitSet referencedTabs, boolean simplePredsOnly) throws StandardException
      Categorize this predicate. Initially, this means building a bit map of the referenced tables for each predicate. If the source of this ColumnReference (at the next underlying level) is not a ColumnReference or a VirtualColumnNode then this predicate will not be pushed down. For example, in: select * from (select 1 from s) a (x) where x = 1 we will not push down x = 1. NOTE: It would be easy to handle the case of a constant, but if the inner SELECT returns an arbitrary expression, then we would have to copy that tree into the pushed predicate, and that tree could contain subqueries and method calls. RESOLVE - revisit this issue once we have views.
      Overrides:
      categorize in class ValueNode
      Parameters:
      referencedTabs - JBitSet with bit map of referenced FromTables
      simplePredsOnly - Whether or not to consider method calls, field references and conditional nodes when building bit map
      Returns:
      boolean Whether or not source.expression is a ColumnReference or a VirtualColumnNode.
      Throws:
      StandardException - Thrown on error

    • remapColumnReferencesToExpressions

      ValueNode remapColumnReferencesToExpressions() throws StandardException
      Remap all ColumnReferences in this tree to be clones of the underlying expression.
      Overrides:
      remapColumnReferencesToExpressions in class ValueNode
      Returns:
      ValueNode The remapped expression tree.
      Throws:
      StandardException - Thrown on error

    • isConstantExpression

      boolean isConstantExpression()
      Return whether or not this expression tree represents a constant expression.
      Overrides:
      isConstantExpression in class ValueNode
      Returns:
      Whether or not this expression tree represents a constant expression.

    • constantExpression

      boolean constantExpression(PredicateList whereClause)
      Description copied from class: ValueNode
      Return whether or not this expression tree represents a constant value. In this case, "constant" means that it will always evaluate to the same thing, even if it includes columns. A column is constant if it is compared to a constant expression.
      Overrides:
      constantExpression in class ValueNode
      Returns:
      True means this expression tree represents a constant value.
      See Also:

    • getReceiverInterfaceName

      String getReceiverInterfaceName() throws StandardException
      Determine the type the binary method is called on. By default, based on the receiver. Override in nodes that use methods on super-interfaces of the receiver's interface, such as comparisons.
      Throws:
      StandardException - Thrown on error

    • getOrderableVariantType

      protected int getOrderableVariantType() throws StandardException
      Return the variant type for the underlying expression. The variant type can be: VARIANT - variant within a scan (method calls and non-static field access) SCAN_INVARIANT - invariant within a scan (column references from outer tables) QUERY_INVARIANT - invariant within the life of a query CONSTANT - immutable
      Overrides:
      getOrderableVariantType in class ValueNode
      Returns:
      The variant type for the underlying expression.
      Throws:
      StandardException - thrown on error

    • acceptChildren

      void acceptChildren(Visitor v) throws StandardException
      Accept the visitor for all visitable children of this node.
      Overrides:
      acceptChildren in class QueryTreeNode
      Parameters:
      v - the visitor
      Throws:
      StandardException - on error

    • isSameNodeKind

      boolean isSameNodeKind(ValueNode o)
      Description copied from class: ValueNode
      Some node classes represent several logical node types (to reduce footprint), which we call kinds. This means that implementations of ValueNode.isEquivalent(ValueNode) cannot always just use instanceof to check if the other node represents the same kind. Hence this method needs to be overridden by all node classes that represent several kinds. This default implementation does not look at kinds. It is only called from implementations of isEquivalent.
      Overrides:
      isSameNodeKind in class ValueNode
      Parameters:
      o - The other value node whose kind we want to compare with.
      Returns:
      true if this and o represent the same logical node type, i.e. kind.

    • isEquivalent

      boolean isEquivalent(ValueNode o) throws StandardException
      Description copied from class: ValueNode
      Tests if this node is equivalent to the specified ValueNode. Two ValueNodes are considered equivalent if they will evaluate to the same value during query execution.

      This method provides basic expression matching facility for the derived class of ValueNode and it is used by the language layer to compare the node structural form of the two expressions for equivalence at bind phase.

      Note that it is not comparing the actual row values at runtime to produce a result; hence, when comparing SQL NULLs, they are considered to be equivalent and not unknown.

      One usage case of this method in this context is to compare the select column expression against the group by expression to check if they are equivalent. e.g.:

      SELECT c1+c2 FROM t1 GROUP BY c1+c2

      In general, node equivalence is determined by the derived class of ValueNode. But they generally abide to the rules below:

      • The two ValueNodes must be of the same node type to be considered equivalent. e.g.: CastNode vs. CastNode - equivalent (if their args also match), ColumnReference vs CastNode - not equivalent.
      • If node P contains other ValueNode(s) and so on, those node(s) must also be of the same node type to be considered equivalent.
      • If node P takes a parameter list, then the number of arguments and its arguments for the two nodes must also match to be considered equivalent. e.g.: CAST(c1 as INTEGER) vs CAST(c1 as SMALLINT), they are not equivalent.
      • When comparing SQL NULLs in this context, they are considered to be equivalent.
      • If this does not apply or it is determined that the two nodes are not equivalent then the derived class of this method should return false; otherwise, return true.
      Specified by:
      isEquivalent in class ValueNode
      Parameters:
      o - the node to compare this ValueNode against.
      Returns:
      true if the two nodes are equivalent, false otherwise.
      Throws:
      StandardException