com.sap.cds.ql

Class Select<T extends StructuredType<?>>

java.lang.Object

com.sap.cds.ql.Select<T>

Type Parameters:

T - the type of the entity set that is the source of this select statement

All Implemented Interfaces:

JSONizable, CQN, CqnEntitySelector, CqnSelect, CqnSource, CqnStatement, CqnToken, Source<T>

public abstract class Select<T extends StructuredType<?>>
extends Object
implements Source<T>, CqnSelect

The Select builder allows to construct CDS QL select statements, which can be executed via the CdsDataStore.

Constructor Summary

Constructors

Constructor and Description
Select()

Method Summary

Modifier and Type	Method and Description
void	accept(CqnVisitor visitor)
abstract Select<T>	byId(Object idValue) Sets the where condition of the select statement, requiring that the value of the single key element of the target entity set is equal to the given idValue.
Select<T>	columns(CqnSelectListItem... items) Sets the projection of the select statement.
Select<T>	columns(Function<T,CqnSelectListItem>... items) Sets the projection of the select statement.
abstract Select<T>	columns(List<CqnSelectListItem> items) Sets the projection of the select statement.
abstract Select<T>	columns(Stream<CqnSelectListItem> items) Sets the projection of the select statement.
abstract Select<T>	columns(String... elements) Sets the projection of the select statement.
static Select<StructuredType<?>>	copy(CqnSelect select) Copies the given CqnSelect into a Select builder.
static Select<StructuredType<?>>	cqn(String cqnSelect) Creates a select statement from a given CQN String.
abstract Select<T>	distinct() Specifies that duplicate query results should be eliminated.
abstract Select<T>	excluding(Collection<String> qualifiedNames) Sets the exclude list of the select statement.
Select<T>	excluding(Function<T,CqnSelectListValue>... items) Sets the exclude list of the select statement.
Select<T>	excluding(String... qualifiedNames) Sets the exclude list of the select statement.
static Select<StructuredType<?>>	from(CdsEntity entity) Creates a select statement to select entries from a specified entity set.
static Select<StructuredType<?>>	from(CdsEntity entity, UnaryOperator<StructuredType<?>> path) Creates a select statement to select entries from a specified entity set.
static <R extends StructuredType<R>,T extends StructuredType<T>> Select<T>	from(Class<R> entity, Function<R,T> path) Creates a select statement to select entries from a specified entity set.
static <T extends StructuredType<T>> Select<T>	from(Class<T> entity) Creates a select statement to select entries from a specified entity set.
static Select<StructuredType<?>>	from(CqnSelect subquery) Creates a select statement to select entries from the result of a given subquery.
static Select<StructuredType<?>>	from(CqnStructuredTypeRef ref) Creates a select statement to select entries from a specified entity set.
static Select<StructuredType<?>>	from(String qualifiedName) Creates a select statement to select entries from a specified entity set.
static Select<StructuredType<?>>	from(String entityName, UnaryOperator<StructuredType<?>> path) Creates a select statement to select entries from a specified entity set.
static <T extends StructuredType<T>> Select<T>	from(StructuredType<T> entity) Creates a select statement to select entries from a specified entity set.
Select<T>	groupBy(CqnElementRef... elements) Sets the group by clause of the select statement.
Select<T>	groupBy(Function<T,CqnSelectListItem>... items) Sets the group by clause of the select statement.
abstract Select<T>	groupBy(List<CqnSelectListItem> items) Sets the group by clause of the select statement.
abstract Select<T>	groupBy(String... elements) Sets the groupBy clause of the select statement.
abstract Select<T>	having(CqnPredicate pred) Sets the having clause of the select statement.
abstract Select<T>	having(Function<T,CqnPredicate> pred) Sets the having clause of the select statement.
abstract Select<T>	inlineCount() Specifies that the total number of root entities matching this query shall be returned along with the result.
Select<T>	limit(Function<T,Value<Integer>> rows) Deprecated. instead use limit(long rows)
Select<T>	limit(Function<T,Value<Integer>> rows, Function<T,Value<Integer>> offset) Deprecated. instead use limit(long rows, long offset)
Select<T>	limit(long rows) Sets the limit of the select statement.
abstract Select<T>	limit(long rows, long offset) Sets the limit and offset of the select statement.
abstract Select<T>	limit(Value<Integer> rows, Value<Integer> offset) Deprecated. instead use limit(long rows, long offset)
abstract Select<T>	lock() Creates a write lock on the selected rows for a default number of seconds specified by DB so that other queries cannot lock or change the data until current transaction is finished.
abstract Select<T>	lock(int timeout) Creates a write lock on the selected rows so that other queries cannot lock or change the data until current transaction is finished.
abstract Select<T>	matching(Map<String,?> values) Sets the where condition of the select statement.
Select<T>	orderBy(CqnSortSpecification... sortSpecs) Sets the orderBy clause of the select statement.
Select<T>	orderBy(Function<T,CqnSortSpecification>... sortSpecs) Sets the orderBy clause of the select statement.
abstract Select<T>	orderBy(List<CqnSortSpecification> sortSpecs) Sets the orderBy clause of the select statement.
abstract Select<T>	orderBy(String... elements) Sets the orderBy clause of the select statement.
abstract Select<T>	search(CqnPredicate pred) Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search predicate.
abstract Select<T>	search(Function<Searchable,Predicate> pred) Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search predicate.
abstract Select<T>	search(Function<Searchable,Predicate> pred, Iterable<String> searchableElements) Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search predicate.
abstract Select<T>	search(String searchTerm) Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search term
abstract Select<T>	search(String searchTerm, Iterable<String> searchableElements) Adds a search filter to this select statement, requiring that any given searchable element of the target entity set matches the given search term.
String	toString()
abstract Select<T>	where(CqnPredicate pred) Sets the where condition of the select statement.
abstract Select<T>	where(Function<T,CqnPredicate> pred) Sets the where condition of the select statement.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.sap.cds.ql.Source

getRoot, getType

Methods inherited from interface com.sap.cds.ql.cqn.CqnSelect

asSelect, columns, excluding, from, getLock, groupBy, hasInlineCount, having, isDistinct, isSelect, search, where

Methods inherited from interface com.sap.cds.ql.cqn.CqnStatement

asDelete, asInsert, asUpdate, asUpsert, isDelete, isInsert, isUpdate, isUpsert, ref

Methods inherited from interface com.sap.cds.JSONizable

toJson

Methods inherited from interface com.sap.cds.ql.cqn.CqnEntitySelector

items, limit, orderBy, ref

Methods inherited from interface com.sap.cds.ql.cqn.CqnToken

tokens

Methods inherited from interface com.sap.cds.ql.cqn.CqnSource

asJoin, asQuery, asRef, isJoin, isQuery, isRef

Constructor Detail

Select

public Select()

Method Detail

from

public static Select<StructuredType<?>> from(String qualifiedName)

Creates a select statement to select entries from a specified entity set.

Parameters:

qualifiedName - the fully qualified name of the CDS entity set

Returns:

the select statement

from

public static Select<StructuredType<?>> from(CqnStructuredTypeRef ref)

Creates a select statement to select entries from a specified entity set.

Parameters:

ref - the ref to the entity to select entries from

Returns:

the select statement

from

public static <T extends StructuredType<T>> Select<T> from(StructuredType<T> entity)

Creates a select statement to select entries from a specified entity set.

Type Parameters:

T - the type of the entity set

Parameters:

entity - the structured type representing the entity set

Returns:

the select statement

from

public static Select<StructuredType<?>> from(String entityName,
                                             UnaryOperator<StructuredType<?>> path)

Creates a select statement to select entries from a specified entity set.

Parameters:

entityName - the root entity name of the path expression

path - a path expression navigating from the root entity to the target entity of the select statement

Returns:

the select statement

from

public static Select<StructuredType<?>> from(CdsEntity entity)

Creates a select statement to select entries from a specified entity set.

Parameters:

entity - the model representation of the entity set obtained by reflection

Returns:

the select statement

See Also:

CdsModel.findEntity(String), CdsModel.entities()

from

public static Select<StructuredType<?>> from(CqnSelect subquery)

Creates a select statement to select entries from the result of a given subquery.

Parameters:

subquery - the subquery to select from

Returns:

the select statement

from

public static Select<StructuredType<?>> from(CdsEntity entity,
                                             UnaryOperator<StructuredType<?>> path)

Creates a select statement to select entries from a specified entity set.

Parameters:

entity - the model representation of the entity set obtained by reflection

path - a path expression navigating from the root entity to the target entity of the select statement

Returns:

the select statement

See Also:

CdsModel.findEntity(String), CdsModel.entities()

from

public static <T extends StructuredType<T>> Select<T> from(Class<T> entity)

Creates a select statement to select entries from a specified entity set.

Type Parameters:

T - the type of the entity set

Parameters:

entity - the static model representation of the entity set

Returns:

the select statement

from

public static <R extends StructuredType<R>,T extends StructuredType<T>> Select<T> from(Class<R> entity,
                                                                                       Function<R,T> path)

Creates a select statement to select entries from a specified entity set.

Type Parameters:

R - the type of the root entity

T - the type of the target entity

Parameters:

entity - the static model representation of the entity set

path - a path expression navigating from the root entity to the target entity of the select statement

Returns:

the select statement

copy

public static Select<StructuredType<?>> copy(CqnSelect select)

Copies the given CqnSelect into a Select builder.

Parameters:

select - the CqnSelect to be copied

Returns:

the modifiable select statement copy

cqn

public static Select<StructuredType<?>> cqn(String cqnSelect)

Creates a select statement from a given CQN String.

Parameters:

cqnSelect - the CQN representation of the select statement

Returns:

the select statement

distinct

public abstract Select<T> distinct()

Specifies that duplicate query results should be eliminated.

Returns:

this select statement

inlineCount

public abstract Select<T> inlineCount()

Specifies that the total number of root entities matching this query shall be returned along with the result. Upon the calculation of the inline count the limit clause will be ignored. Inline count must not be used in combination with distinct, groupy by or having. The count may not exactly equal the actual number of root entities returned by this query.

Returns:

this select statement

columns

@SafeVarargs
public final Select<T> columns(CqnSelectListItem... items)

Sets the projection of the select statement.

Parameters:

items - the CqnSelectListItem(s) that shall be selected

Returns:

this select statement

columns

@SafeVarargs
public final Select<T> columns(Function<T,CqnSelectListItem>... items)

Sets the projection of the select statement.

Parameters:

items - Function(s) providing the CqnSelectListItem(s) that shall be selected

Returns:

this select statement

columns

public abstract Select<T> columns(List<CqnSelectListItem> items)

Sets the projection of the select statement.

Parameters:

items - the CqnSelectListItem(s) that shall be selected

Returns:

this select statement

columns

public abstract Select<T> columns(Stream<CqnSelectListItem> items)

Sets the projection of the select statement.

Parameters:

items - the CqnSelectListItem(s) that shall be selected

Returns:

this select statement

columns

public abstract Select<T> columns(String... elements)

Sets the projection of the select statement. Elements are provided as Strings and can be paths that refer to an element of an entity that is reached via an association or composition, e.g. "author.name".

Parameters:

elements - the element(s) that shall be selected

Returns:

this select statement

excluding

public final Select<T> excluding(String... qualifiedNames)

Sets the exclude list of the select statement.

Parameters:

qualifiedNames - the items that shall be excluded from the projection

Returns:

this select statement

excluding

@SafeVarargs
public final Select<T> excluding(Function<T,CqnSelectListValue>... items)

Sets the exclude list of the select statement.

Parameters:

items - Function(s) providing the CqnSelectListValue(s) that shall be excluded from the projection

Returns:

this select statement

excluding

public abstract Select<T> excluding(Collection<String> qualifiedNames)

Sets the exclude list of the select statement.

Parameters:

qualifiedNames - the items that shall be excluded from the projection

Returns:

this select statement

where

public abstract Select<T> where(Function<T,CqnPredicate> pred)

Sets the where condition of the select statement. The where condition is provided as a function that accepts a model object representing the entity targeted by the select and returning the where condition.

Parameters:

pred - a Function providing the where condition

Returns:

this select statement

where

public abstract Select<T> where(CqnPredicate pred)

Sets the where condition of the select statement.

Parameters:

pred - a CqnPredicate

Returns:

the select statement

matching

public abstract Select<T> matching(Map<String,?> values)

Sets the where condition of the select statement. The where condition is computed from a map of element names of the target entity set to their values, or a CqnParameter. The map entries are transformed into equality predicates and joined via and.

Parameters:

values - the element name to value map defining the where condition

Returns:

this select statement

byId

public abstract Select<T> byId(Object idValue)

Sets the where condition of the select statement, requiring that the value of the single key element of the target entity set is equal to the given idValue.

Parameters:

idValue - the value of the target entity's key element

Returns:

this select statement

search

public abstract Select<T> search(String searchTerm)

Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search term

Parameters:

searchTerm - the value to be searched for

Returns:

this select statement

search

public abstract Select<T> search(Function<Searchable,Predicate> pred)

Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search predicate.

Parameters:

pred - search predicate

Returns:

this select statement

search

public abstract Select<T> search(CqnPredicate pred)

Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search predicate.

Parameters:

pred - search predicate

Returns:

this select statement

search

public abstract Select<T> search(Function<Searchable,Predicate> pred,
                                 Iterable<String> searchableElements)

Adds a search filter to this select statement, requiring that any searchable element of the target entity set matches the given search predicate.

Parameters:

pred - search predicate

searchableElements - elements to be searched in. Overwrites default searchable columns.

Returns:

this select statement

search

public abstract Select<T> search(String searchTerm,
                                 Iterable<String> searchableElements)

Adds a search filter to this select statement, requiring that any given searchable element of the target entity set matches the given search term.

Parameters:

searchTerm - the value to be searched for

searchableElements - elements to be searched in. Overwrites default searchable columns.

Returns:

this select statement

lock

public abstract Select<T> lock(int timeout)

Creates a write lock on the selected rows so that other queries cannot lock or change the data until current transaction is finished.

Parameters:

timeout - maximum number of seconds to wait for [timeout] seconds for the lock acquisition, afterwards the query will fail with the CdsLockTimemoutException

Returns:

this select statement

Throws:

CdsLockTimemoutException - if a lock could not be acquired

lock

public abstract Select<T> lock()

Creates a write lock on the selected rows for a default number of seconds specified by DB so that other queries cannot lock or change the data until current transaction is finished. If lock cannot be acquired, the CdsLockTimemoutException is thrown.

Returns:

this select statement

Throws:

CdsLockTimemoutException - if a lock could not be acquired

groupBy

public final Select<T> groupBy(CqnElementRef... elements)

Sets the group by clause of the select statement.

Parameters:

elements - the elements the select shall be grouped by

Returns:

this select statement

groupBy

@SafeVarargs
public final Select<T> groupBy(Function<T,CqnSelectListItem>... items)

Sets the group by clause of the select statement.

Parameters:

items - Function(s) providing the CqnSelectListItem(s) the select shall be grouped by

Returns:

this select statement

groupBy

public abstract Select<T> groupBy(List<CqnSelectListItem> items)

Sets the group by clause of the select statement.

Parameters:

items - the CqnSelectListItem(s) the select shall be grouped by

Returns:

this select statement

groupBy

public abstract Select<T> groupBy(String... elements)

Sets the groupBy clause of the select statement. Elements are provided as Strings and can be paths that refer to an element of an entity that is reached via an association or composition, e.g. "author.name".

Parameters:

elements - the element(s) the select shall be grouped by

Returns:

this select statement

having

public abstract Select<T> having(CqnPredicate pred)

Sets the having clause of the select statement.

Parameters:

pred - the having predicate condition

Returns:

this select statement

having

public abstract Select<T> having(Function<T,CqnPredicate> pred)

Sets the having clause of the select statement.

Parameters:

pred - Function(s) providing the having predicate condition

Returns:

this select statement

orderBy

@SafeVarargs
public final Select<T> orderBy(Function<T,CqnSortSpecification>... sortSpecs)

Sets the orderBy clause of the select statement.

Parameters:

sortSpecs - Function(s) providing the sort specification

Returns:

this select statement

orderBy

public final Select<T> orderBy(CqnSortSpecification... sortSpecs)

Sets the orderBy clause of the select statement.

Parameters:

sortSpecs - the sort specifications

Returns:

this select statement

orderBy

public abstract Select<T> orderBy(List<CqnSortSpecification> sortSpecs)

Sets the orderBy clause of the select statement.

Parameters:

sortSpecs - the sort specifications

Returns:

this select statement

orderBy

public abstract Select<T> orderBy(String... elements)

Sets the orderBy clause of the select statement. Elements are provided as Strings and can be paths that refer to an element of an entity that is reached via an association or composition, e.g. "author.name".

Parameters:

elements - the elements defining the sort order

Returns:

this select statement

limit

public Select<T> limit(long rows)

Sets the limit of the select statement.

Parameters:

rows - the maximum number of rows returned by the query

Returns:

this select statement

limit

public abstract Select<T> limit(long rows,
                                long offset)

Sets the limit and offset of the select statement.

Parameters:

rows - the maximum number of rows returned by the query

offset - the number of rows that shall be skipped

Returns:

this select statement

limit

@Deprecated
public final Select<T> limit(Function<T,Value<Integer>> rows,
                                         Function<T,Value<Integer>> offset)

Deprecated. instead use limit(long rows, long offset)

Sets the limit and offset of the select statement.

Parameters:

rows - Function(s) providing the maximum number of rows returned by the query

offset - Function(s) providing the number of rows that shall be skipped

Returns:

this select statement

limit

@Deprecated
public final Select<T> limit(Function<T,Value<Integer>> rows)

Deprecated. instead use limit(long rows)

Sets the limit of the select statement.

Parameters:

rows - Function(s) providing the maximum number of rows returned by the query

Returns:

this select statement

limit

@Deprecated
public abstract Select<T> limit(Value<Integer> rows,
                                            Value<Integer> offset)

Deprecated. instead use limit(long rows, long offset)

Sets the limit and offset of the select statement.

Parameters:

rows - the maximum number of rows returned by the query

offset - the number of rows that shall be skipped

Returns:

this select statement

toString

public String toString()

Overrides:

toString in class Object

accept

public void accept(CqnVisitor visitor)

Specified by:

accept in interface CqnSelect

Specified by:

accept in interface CqnSource

Specified by:

accept in interface CqnStatement

Specified by:

accept in interface CqnToken