Returns a Seq of the children of this node.
Returns a Seq of the children of this node. Children should not change. Immutability required for containsChild optimization
Returns the DataType of the result of evaluating this expression.
Returns the DataType of the result of evaluating this expression. It is
invalid to query the dataType of an unresolved expression (i.e., when resolved
== false).
Returns Java source code that can be compiled to evaluate this expression.
Returns Java source code that can be compiled to evaluate this expression. The default behavior is to call the eval method of the expression. Concrete expression implementations should override this to do actual code generation.
a CodegenContext
an ExprCode with unique terms.
an ExprCode containing the Java source code to generate the given expression
Returns the result of evaluating this expression on a given input Row
Returns the tree node at the specified number, used primarily for interactive debugging.
Returns the tree node at the specified number, used primarily for interactive debugging. Numbers for each node can be found in the numberedTreeString.
Note that this cannot return BaseType because logical plan's plan node might return physical plan for innerChildren, e.g. in-memory relation logical plan node has a reference to the physical plan node it is referencing.
Returns a string representing the arguments to this node, minus any children
Returns a string representing the arguments to this node, minus any children
Returns a 'scala code' representation of this TreeNode
and its children.
Returns a 'scala code' representation of this TreeNode
and its children. Intended for use
when debugging where the prettier toString function is obfuscating the actual structure. In the
case of 'pure' TreeNodes
that only contain primitives and other TreeNodes, the result can be
pasted in the REPL to build an equivalent Tree.
Returns an expression where a best effort attempt has been made to transform this
in a way
that preserves the result but removes cosmetic variations (case sensitivity, ordering for
commutative operations, etc.) See Canonicalize for more details.
Returns an expression where a best effort attempt has been made to transform this
in a way
that preserves the result but removes cosmetic variations (case sensitivity, ordering for
commutative operations, etc.) See Canonicalize for more details.
deterministic
expressions where this.canonicalized == other.canonicalized
will always
evaluate to the same result.
Checks the input data types, returns TypeCheckResult.success
if it's valid,
or returns a TypeCheckResult
with an error message if invalid.
Checks the input data types, returns TypeCheckResult.success
if it's valid,
or returns a TypeCheckResult
with an error message if invalid.
Note: it's not valid to call this method until childrenResolved == true
.
Returns true if all the children of this expression have been resolved to a specific schema and false if any still contains any unresolved placeholders.
Returns a Seq containing the result of applying a partial function to all elements in this tree on which the function is defined.
Returns a Seq containing the result of applying a partial function to all elements in this tree on which the function is defined.
Finds and returns the first TreeNode of the tree for which the given partial function is defined (pre-order), and applies the partial function to it.
Returns a Seq containing the leaves in this tree.
Returns a Seq containing the leaves in this tree.
Returns true when the current expression always return the same result for fixed inputs from children.
Returns true when the current expression always return the same result for fixed inputs from children.
Note that this means that an expression should be considered as non-deterministic if: - it relies on some mutable internal state, or - it relies on some implicit input that is not part of the children expression list. - it has non-deterministic child or children.
An example would be SparkPartitionID
that relies on the partition id returned by TaskContext.
By default leaf expressions are deterministic as Nil.forall(_.deterministic) returns true.
Faster version of equality which short-circuits when two treeNodes are the same instance.
Faster version of equality which short-circuits when two treeNodes are the same instance.
We don't just override Object.equals, as doing so prevents the scala compiler from
generating case class equals
methods
Find the first TreeNode that satisfies the condition specified by f
.
Returns a Seq by applying a function to all nodes in this tree and using the elements of the resulting collections.
Returns a Seq by applying a function to all nodes in this tree and using the elements of the resulting collections.
Returns true when an expression is a candidate for static evaluation before the query is executed.
Returns true when an expression is a candidate for static evaluation before the query is executed.
The following conditions are used to determine suitability for constant folding:
Runs the given function on this node and then recursively on children.
Runs the given function recursively on children then on this node.
Returns an ExprCode, that contains the Java source code to generate the result of evaluating the expression on an input row.
Returns an ExprCode, that contains the Java source code to generate the result of evaluating the expression on an input row.
a CodegenContext
ExprCode
Appends the string represent of this node and its children to the given StringBuilder.
Appends the string represent of this node and its children to the given StringBuilder.
The i
-th element in lastChildren
indicates whether the ancestor of the current node at
depth i + 1
is the last child of its own parent node. The depth of the root node is 0, and
lastChildren
for the root node should be empty.
Note that this traversal (numbering) order must be the same as getNodeNumbered.
All the nodes that should be shown as a inner nested tree of this node.
All the nodes that should be shown as a inner nested tree of this node. For example, this can be used to show sub-queries.
Creates a copy of this type of tree node after a transformation.
Creates a copy of this type of tree node after a transformation. Must be overridden by child classes that have constructor arguments that are not present in the productIterator.
the new product arguments.
Returns a Seq containing the result of applying the given function to each node in this tree in a preorder traversal.
Returns a Seq containing the result of applying the given function to each node in this tree in a preorder traversal.
the function to be applied.
Returns a copy of this node where f
has been applied to all the nodes children.
Returns a copy of this node where f
has been applied to all the nodes children.
Efficient alternative to productIterator.map(f).toArray
.
Efficient alternative to productIterator.map(f).toArray
.
Returns the name of this type of TreeNode.
Returns the name of this type of TreeNode. Defaults to the class name. Note that we remove the "Exec" suffix for physical operators here.
Returns a string representation of the nodes in this tree, where each operator is numbered.
Returns a string representation of the nodes in this tree, where each operator is numbered. The numbers can be used with TreeNode.apply to easily access specific subtrees.
The numbers are based on depth-first traversal of the tree (with innerChildren traversed first before children).
Args to the constructor that should be copied, but not transformed.
Args to the constructor that should be copied, but not transformed. These are appended to the transformed args automatically by makeCopy
Returns the tree node at the specified number, used primarily for interactive debugging.
Returns the tree node at the specified number, used primarily for interactive debugging. Numbers for each node can be found in the numberedTreeString.
This is a variant of apply that returns the node as BaseType (if the type matches).
Returns a user-facing string representation of this expression's name.
Returns a user-facing string representation of this expression's name. This should usually match the name of the function in SQL.
Returns true
if this expression and all its children have been resolved to a specific schema
and input data types checking passed, and false
if it still contains any unresolved
placeholders or has data types mismatch.
Returns true
if this expression and all its children have been resolved to a specific schema
and input data types checking passed, and false
if it still contains any unresolved
placeholders or has data types mismatch.
Implementations of expressions should override this if the resolution of this type of
expression involves more than just the resolution of its children and type checking.
Returns true when two expressions will always compute the same result, even if they differ cosmetically (i.e.
Returns true when two expressions will always compute the same result, even if they differ cosmetically (i.e. capitalization of names in attributes may be different).
See Canonicalize for more details.
Returns a hashCode
for the calculation performed by this expression.
Returns a hashCode
for the calculation performed by this expression. Unlike the standard
hashCode
, an attempt has been made to eliminate cosmetic differences.
See Canonicalize for more details.
ONE line description of this node.
ONE line description of this node.
Returns SQL representation of this expression.
Returns SQL representation of this expression. For expressions extending NonSQLExpression, this method may return an arbitrary user facing string.
The arguments that should be included in the arg string.
The arguments that should be included in the arg string. Defaults to the productIterator
.
Returns a copy of this node where rule
has been recursively applied to the tree.
Returns a copy of this node where rule
has been recursively applied to the tree.
When rule
does not apply to a given node it is left unchanged.
Users should not expect a specific directionality. If a specific directionality is needed,
transformDown or transformUp should be used.
the function use to transform this nodes children
Returns a copy of this node where rule
has been recursively applied to it and all of its
children (pre-order).
Returns a copy of this node where rule
has been recursively applied to it and all of its
children (pre-order). When rule
does not apply to a given node it is left unchanged.
the function used to transform this nodes children
Returns a copy of this node where rule
has been recursively applied first to all of its
children and then itself (post-order).
Returns a copy of this node where rule
has been recursively applied first to all of its
children and then itself (post-order). When rule
does not apply to a given node, it is left
unchanged.
the function use to transform this nodes children
Returns a string representation of the nodes in this tree
Returns a string representation of the nodes in this tree
ONE line description of this node with more information
ONE line description of this node with more information
Returns a copy of this node with the children replaced.
Returns a copy of this node with the children replaced. TODO: Validate somewhere (in debug mode?) that children are ordered correctly.
An expression in Catalyst.
If an expression wants to be exposed in the function registry (so users can call it with "name(arguments...)", the concrete implementation must be a case class whose constructor arguments are all Expressions types. See Substring for an example.
There are a few important traits:
- Nondeterministic: an expression that is not deterministic. - Unevaluable: an expression that is not supposed to be evaluated. - CodegenFallback: an expression that does not have code gen implemented and falls back to interpreted mode.
- LeafExpression: an expression that has no child. - UnaryExpression: an expression that has one child. - BinaryExpression: an expression that has two children. - TernaryExpression: an expression that has three children. - BinaryOperator: a special case of BinaryExpression that requires two children to have the same output data type.