Query (Grakn 0.10.0 API)

java.lang.Object
- ai.grakn.graql.internal.reasoner.query.Query

Direct Known Subclasses:

AtomicQuery, ReasonerMatchQuery
```
public class Query
extends Object
```
Base reasoner query providing resolution and atom handling facilities for conjunctive graql queries.

Author:

Kasper Piskorski

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`Query(Atom atom, Set<VarName> vars)`
	`Query(MatchQuery query, GraknGraph graph)`
	`Query(Query q)`
	`Query(String query, GraknGraph graph)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`addAtom(Atomic atom)`
`void`	`addAtomConstraints(Set<? extends Atomic> cstrs)` adds a set of constraints (types, predicates) to the atom set
`boolean`	`containsAtom(Atomic atom)`
`boolean`	`containsEquivalentAtom(Atomic atom)`
`void`	`DBlookup()` resolve the query by performing a db lookup
`boolean`	`equals(Object obj)`
`QueryAnswers`	`getAnswers()`
`Set<Atomic>`	`getAtoms()`
`Set<NotEquals>`	`getFilters()`
`IdPredicate`	`getIdPredicate(VarName var)`
`Set<IdPredicate>`	`getIdPredicates()`
`MatchQuery`	`getMatchQuery()`
`QueryAnswers`	`getNewAnswers()`
`Conjunction<PatternAdmin>`	`getPattern()`
`Set<Atom>`	`getResources()`
`Set<VarName>`	`getSelectedNames()`
`Set<Atom>`	`getTypeConstraints()`
`Set<Predicate>`	`getValuePredicates()`
`Set<VarName>`	`getVarSet()`
`Map<VarName,Type>`	`getVarTypeMap()`
`GraknGraph`	`graph()`
`int`	`hashCode()`
`boolean`	`isEquivalent(Query q)`
`boolean`	`isRuleResolvable()`
`void`	`lookup(QueryCache cache)` resolve the query by performing either a db or memory lookup, depending on which is more appropriate
`void`	`memoryLookup(QueryCache cache)` resolve the query by performing a memory (cache) lookup
`void`	`propagateAnswers(QueryCache cache)` propagate answers to relation resolutions in the cache
`boolean`	`removeAtom(Atomic atom)`
`java.util.stream.Stream<Map<VarName,Concept>>`	`resolve(boolean materialise)` resolves the query
`void`	`selectAppend(Set<VarName> vars)` append to select variables
`Set<Atom>`	`selectAtoms()` atom selection function
`String`	`toString()`
`void`	`unify(Map<VarName,VarName> unifiers)` change each variable occurrence according to provided mappings (apply unifiers {[from, to]_i})
`void`	`unify(VarName from, VarName to)` change each variable occurrence in the query (apply unifier [from/to])

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - Query
```
public Query(MatchQuery query,
             GraknGraph graph)
```
  - Query
```
public Query(String query,
             GraknGraph graph)
```
  - Query
```
public Query(Query q)
```
  - Query
```
protected Query(Atom atom,
                Set<VarName> vars)
```
- Method Detail
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - getSelectedNames
```
public Set<VarName> getSelectedNames()
```
  - selectAppend
```
public void selectAppend(Set<VarName> vars)
```
    append to select variables
    
    Parameters:
    
    vars - variables to append
  - graph
```
public GraknGraph graph()
```
  - getPattern
```
public Conjunction<PatternAdmin> getPattern()
```
  - isRuleResolvable
```
public boolean isRuleResolvable()
```
    Returns:
    
    true if any of the atoms constituting the query can be resolved through a rule
  - getAnswers
```
public QueryAnswers getAnswers()
```
  - getNewAnswers
```
public QueryAnswers getNewAnswers()
```
  - lookup
```
public void lookup(QueryCache cache)
```
    resolve the query by performing either a db or memory lookup, depending on which is more appropriate
    
    Parameters:
    
    cache - container of already performed query resolutions
  - DBlookup
```
public void DBlookup()
```
    resolve the query by performing a db lookup
  - memoryLookup
```
public void memoryLookup(QueryCache cache)
```
    resolve the query by performing a memory (cache) lookup
    
    Parameters:
    
    cache - container of already performed query resolutions
  - propagateAnswers
```
public void propagateAnswers(QueryCache cache)
```
    propagate answers to relation resolutions in the cache
    
    Parameters:
    
    cache - container of already performed query resolutions
  - getAtoms
```
public Set<Atomic> getAtoms()
```
    Returns:
    
    atom set constituting this query
  - getIdPredicates
```
public Set<IdPredicate> getIdPredicates()
```
    Returns:
    
    set of id predicates contained in this query
  - getValuePredicates
```
public Set<Predicate> getValuePredicates()
```
    Returns:
    
    set of value predicates contained in this query
  - getResources
```
public Set<Atom> getResources()
```
    Returns:
    
    set of resource atoms contained in this query
  - getTypeConstraints
```
public Set<Atom> getTypeConstraints()
```
    Returns:
    
    set of atoms constituting constraints (by means of types) for this atom
  - getFilters
```
public Set<NotEquals> getFilters()
```
    Returns:
    
    set of filter atoms (currently only NotEquals) contained in this query
  - getVarSet
```
public Set<VarName> getVarSet()
```
    Returns:
    
    set of variables appearing in this query
  - containsAtom
```
public boolean containsAtom(Atomic atom)
```
    Parameters:
    
    atom - in question
    
    Returns:
    
    true if atom is contained in the query
  - containsEquivalentAtom
```
public boolean containsEquivalentAtom(Atomic atom)
```
    Parameters:
    
    atom - in question
    
    Returns:
    
    true if query contains an equivalent atom
  - unify
```
public void unify(VarName from,
                  VarName to)
```
    change each variable occurrence in the query (apply unifier [from/to])
    
    Parameters:
    
    from - variable name to be changed
    
    to - new variable name
  - unify
```
public void unify(Map<VarName,VarName> unifiers)
```
    change each variable occurrence according to provided mappings (apply unifiers {[from, to]_i})
    
    Parameters:
    
    unifiers - contain unifiers (variable mappings) to be applied
  - getMatchQuery
```
public MatchQuery getMatchQuery()
```
    Returns:
    
    corresponding MatchQuery
  - getVarTypeMap
```
public Map<VarName,Type> getVarTypeMap()
```
    Returns:
    
    map of variable name - type pairs
  - getIdPredicate
```
public IdPredicate getIdPredicate(VarName var)
```
    Parameters:
    
    var - variable name
    
    Returns:
    
    id predicate for the specified var name if any
  - addAtom
```
public boolean addAtom(Atomic atom)
```
    Parameters:
    
    atom - to be added
    
    Returns:
    
    true if the atom set did not already contain the specified atom
  - removeAtom
```
public boolean removeAtom(Atomic atom)
```
    Parameters:
    
    atom - to be removed
    
    Returns:
    
    true if the atom set contained the specified atom
  - addAtomConstraints
```
public void addAtomConstraints(Set<? extends Atomic> cstrs)
```
    adds a set of constraints (types, predicates) to the atom set
    
    Parameters:
    
    cstrs - set of constraints
  - selectAtoms
```
public Set<Atom> selectAtoms()
```
    atom selection function
    
    Returns:
    
    selected atoms
  - isEquivalent
```
public boolean isEquivalent(Query q)
```
    Parameters:
    
    q - query to be compared with
    
    Returns:
    
    true if two queries are alpha-equivalent
  - resolve
```
public java.util.stream.Stream<Map<VarName,Concept>> resolve(boolean materialise)
```
    resolves the query
    
    Parameters:
    
    materialise - materialisation flag
    
    Returns:
    
    stream of answers

Class Query

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Query

Query

Query

Query

Method Detail

equals

hashCode

toString

getSelectedNames

selectAppend

graph

getPattern

isRuleResolvable

getAnswers

getNewAnswers

lookup

DBlookup

memoryLookup

propagateAnswers

getAtoms

getIdPredicates

getValuePredicates

getResources

getTypeConstraints

getFilters

getVarSet

containsAtom

containsEquivalentAtom

unify

unify

getMatchQuery

getVarTypeMap

getIdPredicate

addAtom

removeAtom

addAtomConstraints

selectAtoms

isEquivalent

resolve