WOQL Class Reference Guide

WOQL Schema

This is the WOQL schema. It gives a complete specification of the syntax of the WOQL query language. This allows WOQL queries to be checked for syntactic correctness, helps to prevent errors and detect conflicts in merge of queries, and allows the storage and retrieval of queries so that queries can be associated with data products.

Authored by: Gavin Mendel-Gleason

Syntax is listed in alphabetical order.

AddData

Add a (terminal) edge with a data value.

Class: AddData

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`DataValue`	A datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

AddLink

Add an edge which links between nodes in the graph.

Class: AddLink

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`NodeValue`	A URI or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

AddTriple

Specify an edge to add to the graph.

Class: AddTriple

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`Value`	A URI, datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

AddedData

Specify an edge pattern with data value which was added in *this* commit*.

Class: AddedData

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`DataValue`	A datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

AddedLink

Specify an edge pattern which links between nodes at *this* commit.

Class: AddedLink

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`NodeValue`	A URI or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

AddedTriple

Specify an edge pattern which was *added* at *this commit*.

Class: AddedTriple

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`Value`	A URI, datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

And

A conjunction of queries which must all have a solution.

Class: And

Super class: Query

Properties:

Property	Range	Desc
`and`	`Query`	List of queries which must hold.

ArithmeticExpression

An abstract class specifying the AST super-class of all arithemtic expressions. It is a subdocument

Class: ArithmeticExpression

ArithmeticValue

A variable or node. It is a subdocument

Class: ArithmeticValue

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`data`	`xsd:anySimpleType`	An xsd data type value.
`variable`	`xsd:string`	A variable.

Column

Description pending.

Class: Column

Concatenate

Concatenate a list of strings.

Class: Concatenate

Super class: Query

Properties:

Property	Range	Desc
`list`	`DataValue`	The list to concatenate.
`result`	`DataValue`	The result string.

Count

Counts the number of solutions of a query.

Class: Count

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query from which to obtain the count.
`count`	`DataValue`	The count of the number of solutions.

Data

Specify an edge pattern which is terminal, and provides a data value association.

Class: Data

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`DataValue`	A data type or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

DataValue

A variable or node. It is a subdocument

Class: DataValue

Properties:

Property	Range	Desc
`data`	`xsd:anySimpleType`	An xsd data type value.
`variable`	`xsd:string`	A variable.
`list`	`DataValue`	A list of datavalues

DeleteDocument

Delete a document from the graph.

Class: DeleteDocument

Super class: Query

Properties:

Property	Range	Desc
`identifier`	`NodeValue`	An identifier specifying the documentation location to delete.

DeleteLink

Delete an edge linking nodes.

Class: DeleteLink

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge. The variable must be bound.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge. The variable must be bound.
`object`	`NodeValue`	A URI or variable which is the target or object of the graph edge. The variable must be bound.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

DeleteTriple

Specify an edge pattern to remove from the graph.

Class: DeleteTriple

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`Value`	A URI, datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

DeletedLink

An edge pattern specifying a link beween nodes deleted *at this commit*.

Class: DeletedLink

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`NodeValue`	A URI or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

DeletedTriple

Specify an edge pattern which was *deleted* at *this commit*.

Class: DeletedTriple

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`Value`	A URI, datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

Distinct

Ensure variables listed result in distinct solutions.

Class: Distinct

Super class: Query

Properties:

Property	Range	Desc
`variables`	`xsd:string`	The variables which must be distinct from the query.
`query`	`Query`	The query which will be run prior to selection.

Div

Integer divide two numbers.

Class: Div

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`left`	`ArithmeticExpression`	First operand of div.
`right`	`ArithmeticExpression`	Second operand of div.

Divide

Divide two numbers.

Class: Divide

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`left`	`ArithmeticExpression`	First operand of divide.
`right`	`ArithmeticExpression`	Second operand of divide.

Dot

Extract the value of a key in a bound document.

Class: Dot

Super class: Query

Properties:

Property	Range	Desc
`star`	`undefined`	A path patterns.

Equals

True whenever 'left' is the same as 'right'. Performs unification.

Class: Equals

Super class: Query

Properties:

Property	Range	Desc
`child`	`undefined`	A URI, data value or variable.
`parent`	`undefined`	A URI, data value or variable.

Eval

Evaluate an arithmetic expression to obtain a result.

Class: Eval

Super class: Query

Properties:

Property	Range	Desc
`expression`	`ArithmeticExpression`	The expression to be evaluated.
`result`	`ArithmeticValue`	The numeric result.

Exp

Exponentiate a number.

Class: Exp

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`left`	`ArithmeticExpression`	The base.
`right`	`ArithmeticExpression`	The exponent.

Floor

Find the integral part of a number.

Class: Floor

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`argument`	`ArithmeticExpression`	The number to floor.

FormatType

Description pending.

Class: FormatType

From

Change the default read graph (between instance/schema).

Class: From

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The subquery with a new default graph.
`graph_filter`	`xsd:string`	The graph filter: 'schema' or 'instance' or '*'.

Get

Description pending.

Class: Get

Super class: Query

Greater

Predicate determining if one thing is greater than another according to natural ordering.

Class: Greater

Super class: Query

Properties:

Property	Range	Desc
`left`	`DataValue`	The greater element.
`right`	`DataValue`	The lesser element.

GroupBy

Group a query into a list with each element of the list specified by 'template' using a given variable set for the group.

Class: GroupBy

Super class: Query

Properties:

Property	Range	Desc
`template`	`xsd:string`	The template of elements in the result list.
`group_by`	`xsd:string`	The variables which should be grouped into like solutions.
`query`	`Query`	The subquery providing the solutions for the grouping.
`grouped`	`Value`	The final list of templated solutions.

HashKey

Generates a key identical to those generated automatically by 'HashKey' specifications.

Class: HashKey

Super class: Query

Properties:

Property	Range	Desc
`base`	`DataValue`	The URI base to the left of the key.
`key_list`	`DataValue`	List of data elements required to generate the key.
`uri`	`NodeValue`	The resulting URI.

If

A conditional which runs the then clause for every success from the test clause, otherwise runs the else clause.

Class: If

Super class: Query

Properties:

Property	Range	Desc
`test`	`Query`	A query which will provide bindings for the then clause.
`then`	`Query`	A query which will run for every solution of test with associated bindings.
`else`	`Query`	A query which runs whenever test fails.

Immediately

Attempts to perform all side-effecting operations immediately. Can have strange non-backtracking effects but can also increase performance. Use at your own risk.

Class: Immediately

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query from which to obtain the side-effects.

Indicator

Description pending.

Class: Indicator

Into

Change the default write graph (between instance/schema).

Class: Into

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The subquery with a new default write graph.
`graph`	`xsd:string`	The graph filter: schema or instance.

InversePathPredicate

A predicate to traverse *backwards*.

Class: InversePathPredicate

Super class: PathPattern

Properties:

Property	Range	Desc
`predicate`	`xsd:string`	The predicate to use in reverse direction in the pattern traversal.

IsA

Test (or generate) the type of an element.

Class: IsA

Super class: Query

Properties:

Property	Range	Desc
`element`	`NodeValue`	The element to test.
`type`	`NodeValue`	The type of the element.

Join

Join a list of strings using 'separator'.

Class: Join

Super class: Query

Properties:

Property	Range	Desc
`list`	`DataValue`	The list to concatenate.
`separator`	`DataValue`	The separator between each joined string
`result`	`DataValue`	The result string.

Length

The length of a list.

Class: Length

Super class: Query

Properties:

Property	Range	Desc
`list`	`DataValue`	The list of which to find the length.
`length`	`DataValue`	The length of the list.

Less

Predicate determining if one thing is less than another according to natural ordering.

Class: Less

Super class: Query

Properties:

Property	Range	Desc
`left`	`DataValue`	The lesser element.
`right`	`DataValue`	The greater element.

LexicalKey

Generates a key identical to those generated automatically by 'LexicalKey' specifications.

Class: LexicalKey

Super class: Query

Properties:

Property	Range	Desc
`base`	`DataValue`	The URI base to the left of the key.
`key_list`	`DataValue`	List of data elements required to generate the key.
`uri`	`NodeValue`	The resulting URI.

Like

Distance between strings, similar to a Levenstein distance.

Class: Like

Super class: Query

Properties:

Property	Range	Desc
`left`	`DataValue`	The first string.
`right`	`DataValue`	The second string.
`similarity`	`DataValue`	Number between -1 and 1 which gives a scale for similarity.

Limit

Limit a query to a particular maximum number of solutions specified by 'limit'. Can be used with start to perform paging.

Class: Limit

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query to perform.
`limit`	`xsd:nonNegativeInteger`	Maximum number of solutions.

Link

Specify an edge pattern which is not terminal, but a link between objects.

Class: Link

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`NodeValue`	A URI or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

Lower

Lowercase a string.

Class: Lower

Super class: Query

Properties:

Property	Range	Desc
`mixed`	`DataValue`	The mixed case string.
`uppser`	`undefined`	The lower case string.

Member

Generate or test every element of a list.

Class: Member

Super class: Query

Properties:

Property	Range	Desc
`member`	`DataValue`	The element to test for membership or to supply as generated.
`list`	`DataValue`	The list of elements against which to generate or test.

Minus

Subtract two numbers.

Class: Minus

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`left`	`ArithmeticExpression`	First operand of minus.
`right`	`ArithmeticExpression`	Second operand of minus.

NamedParametricQuery

A named parametric query which names a specific query for later retrieval and re-use and allows the specification of bindings for a specific set of variables in the query.

Class: NamedParametricQuery

Properties:

Property	Range	Desc
`name`	`xsd:string`	The name of the NamedParametricQuery to be retrieved.
`parameters`	`xsd:string`	Variable name list for auxilliary bindings.
`query`	`Query`	The query AST as WOQL JSON.

NamedQuery

A named query names a specific query for later retrieval and re-use.

Class: NamedQuery

Properties:

Property	Range	Desc
`name`	`xsd:string`	The name of the NamedQuery to be retrieved
`query`	`Query`	The query AST as WOQL JSON

NodeValue

A variable or node. It is a subdocument

Class: NodeValue

Properties:

Property	Range	Desc
`node`	`xsd:string`	A URI representing a resource.
`variable`	`xsd:string`	A variable.

Not

The negation of a query. Provides no solution bindings, but will succeed if its sub-query fails.

Class: Not

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query which must not hold.

Once

Obtains exactly one solution from a query. Simliar to a limit of 1.

Class: Once

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query from which to obtain a solution.

Optional

A query which will succeed (without bindings) even in the case of failure.

Class: Optional

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query to run.

Or

A disjunction of queries any of which can provide a solution.

Class: Or

Super class: Query

Properties:

Property	Range	Desc
`or`	`Query`	List of queries which may hold.

Order

Description pending.

Class: Order

OrderBy

Orders query results according to an ordering specification.

Class: OrderBy

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The base query giving the solutions to order.
`ordering`	`OrderTemplate`	A specification of the ordering of solutions.

OrderTemplate

The order template, consisting of the variable and ordering direction. It is a subdocument

Class: OrderTemplate

Properties:

Property	Range	Desc
`order`	`Order`	An enum either 'asc' or 'desc'.
`variable`	`xsd:string`	The variable to order.

Pad

Pad a string.

Class: Pad

Super class: Query

Properties:

Property	Range	Desc
`string`	`DataValue`	The starting string.
`char`	`DataValue`	The padding character.
`times`	`DataValue`	The number of times to repeat the padding character.
`result`	`DataValue`	The result of the padding as a string.

Path

Find a path through the graph according to 'pattern'. This 'pattern' is a regular graph expression which avoids cycles.

Class: Path

Super class: Query

Properties:

Property	Range	Desc
`subject`	`Value`	The starting node.
`pattern`	`PathPattern`	The pattern which describes how to traverse edges.
`object`	`Value`	The ending node.
`path`	`Value`	An optional list of edges traversed.

PathOr

A set of patterns in which each of the patterns can result in objects starting from our current subject set.

Class: PathOr

Super class: PathPattern

Properties:

Property	Range	Desc
`or`	`PathPattern`	A disjunction of path patterns.

PathPattern

Description pending.

Class: PathPattern

PathPlus

The path pattern specified by 'plus' must hold one or more times in succession.

Class: PathPlus

Super class: PathPattern

Properties:

Property	Range	Desc
`plus`	`PathPattern`	A path patterns.

PathPredicate

A predicate to traverse.

Class: PathPredicate

Super class: PathPattern

Properties:

Property	Range	Desc
`predicate`	`xsd:string`	The predicate to use in the pattern traversal.

PathSequence

A sequence of patterns in which each of the patterns in the list must result in objects which are subjects of the next pattern in the list.

Class: PathSequence

Super class: PathPattern

Properties:

Property	Range	Desc
`sequence`	`PathPattern`	A sequence of path patterns.

PathStar

The path pattern specified by 'star' may hold zero or more times in succession.

Class: PathStar

Super class: PathPattern

Properties:

Property	Range	Desc
`star`	`PathPattern`	A path patterns.

PathTimes

The path pattern specified by 'times' may hold 'from' to 'to' times in succession.

Class: PathTimes

Super class: PathPattern

Properties:

Property	Range	Desc
`star`	`undefined`	A path patterns.

Plus

Add two numbers.

Class: Plus

Super class: ArithmeticExpression

Properties:

Property	Range	Desc
`left`	`ArithmeticExpression`	First operand of add.
`right`	`ArithmeticExpression`	Second operand of add.

Put

Description pending.

Class: Put

Super class: Query

Query

An abstract class which represents an arbitrary query AST. It is a subdocument

Class: Query

QueryResource

Description pending.

Class: QueryResource

RandomKey

Generates a key identical to those generated automatically by 'RandomKey' specifications.

Class: RandomKey

Super class: Query

Properties:

Property	Range	Desc
`base`	`DataValue`	The URI base to the left of the key.
`uri`	`NodeValue`	The resulting URI.

ReadDocument

Read a full document from an identifier.

Class: ReadDocument

Super class: Query

Properties:

Property	Range	Desc
`document`	`DataValue`	Variable which will be bound to the document.
`identifier`	`NodeValue`	The URI of the document to load.

Regexp

Test a string against a PCRE style regex pattern.

Class: Regexp

Super class: Query

Properties:

Property	Range	Desc
`pattern`	`DataValue`	The PCRE style pattern.
`string`	`DataValue`	The string to test.
`result`	`DataValue`	An optional result list of matches.

Select

Select specific variables from a query to return.

Class: Select

Super class: Query

Properties:

Property	Range	Desc
`variables`	`xsd:string`	The variables to select from the query.
`query`	`Query`	The query which will be run prior to selection.

Size

Size of a database in magic units (bytes?).

Class: Size

Super class: Query

Properties:

Property	Range	Desc
`resource`	`xsd:string`	The resource to obtain the size of.
`size`	`DataValue`	The size.

Source

Description pending.

Class: Source

Split

Split a string.

Class: Split

Super class: Query

Properties:

Property	Range	Desc
`string`	`DataValue`	The starting string.
`pattern`	`DataValue`	The splitting pattern.
`list`	`DataValue`	The result list of strings.

Start

Start a query at the nth solution specified by 'start'. Allows resumption and paging of queries.

Class: Start

Super class: Query

Properties:

Property	Range	Desc
`query`	`Query`	The query to perform.
`start`	`xsd:nonNegativeInteger`	The numbered solution to start at.

Substring

Finds the boundaries of a substring in a string.

Class: Substring

Super class: Query

Properties:

Property	Range	Desc
`string`	`DataValue`	The super-string as data or variable.
`substring`	`DataValue`	The super-string as data or variable.
`length`	`DataValue`	The length of the string as an integer or variable.
`before`	`DataValue`	The count of characters before substring as an integer or variable.
`after`	`DataValue`	The count of characters after substring as an integer or variable.

Subsumption

Provides class subsumption (the inheritance model) according to the schema design. True whenver 'child' is a child of 'parent'. Can be used as a generator or a check.

Class: Subsumption

Super class: Query

Properties:

Property	Range	Desc
`child`	`NodeValue`	The child class as a URI or variable.
`parent`	`NodeValue`	The parent class as a URI or variable

Sum

Sum a list of strings.

Class: Sum

Super class: Query

Properties:

Property	Range	Desc
`list`	`DataValue`	The list of numbers to sum.
`result`	`DataValue`	The result of the sum as a number.

Trim

Trims whitespace from 'untrimmed'.

Class: Trim

Super class: Query

Properties:

Property	Range	Desc
`untrimmed`	`DataValue`	The untrimmed string.
`trimmed`	`DataValue`	The string to be trimmed.

Triple

Specify an edge pattern in the graph.

Class: Triple

Super class: Query

Properties:

Property	Range	Desc
`subject`	`NodeValue`	A URI or variable which is the source or subject of the graph edge.
`predicate`	`NodeValue`	A URI or variable which is the edge-label or predicate of the graph edge.
`object`	`Value`	A URI, datatype or variable which is the target or object of the graph edge.
`graph`	`xsd:string`	An optional graph (either 'instance' or 'schema')

TripleCount

The number of edges in a database.

Class: TripleCount

Super class: Query

Properties:

Property	Range	Desc
`resource`	`xsd:string`	The resource to obtain the edges from.
`count`	`DataValue`	The count of edges.

True

The query which is always true.

Class: True

Super class: Query

Typecast

Casts one type as another if possible.

Class: Typecast

Super class: Query

Properties:

Property	Range	Desc
`value`	`Value`	The value to cast.
`type`	`NodeValue`	The type to which to cast.
`result`	`Value`	The resulting value after cast.

UpdateDocument

Update a document in the graph.

Class: UpdateDocument

Super class: Query

Properties:

Property	Range	Desc
`document`	`DataValue`	The document to update. Must either have an '@id' or have a class specified key.
`identifier`	`NodeValue`	An optional returned identifier specifying the documentation location.

Upper

Uppercase a string.

Class: Upper

Super class: Query

Properties:

Property	Range	Desc
`mixed`	`DataValue`	The mixed case string.
`uppser`	`undefined`	The upper case string.

Using

Select a specific collection for query.

Class: Using

Super class: Query

Properties:

Property	Range	Desc
`collection`	`xsd:string`	The resource over which to run the query.
`query`	`Query`	The query which will be run on the selected collection.

Value

A variable, node or data point. It is a subdocument

Class: Value

Properties:

Property	Range	Desc
`node`	`xsd:string`	A URI representing a resource.
`variable`	`xsd:string`	A variable.
`list`	`Value`	A list of datavalues
`data`	`xsd:anySimpleType`	An xsd data type value.