Class QueryUtils

java.lang.Object

ubic.gemma.persistence.util.QueryUtils

public class QueryUtils
extends Object

Utilities for Query.

Author:

poirigui

Field Summary

Fields

Modifier and Type	Field	Description
static final int	MAX_PARAMETER_LIST_SIZE	Largest parameter list size for which optimizeParameterList(Collection) should be used.

Constructor Summary

Constructors

Constructor	Description
QueryUtils()

Method Summary

Modifier and Type	Method	Description
static <T extends Identifiable> List<List<T>>	batchIdentifiableParameterList(Collection<T> list, int batchSize)
static <T extends Comparable<T>> List<List<T>>	batchParameterList(Collection<T> list, int batchSize)	Partition a parameter list into a collection of batches of a given size.
static <T> Stream<T>	createStream(SessionFactory sessionFactory, Function<Session, Stream<T>> streamFactory, boolean createNewSession)	Safely create a Stream from either the current or a new Session.
static String	escapeLike(String s)
static <S extends Comparable<S>> int	executeUpdateByBatch(Query query, String batchParam, Collection<S> list, int batchSize)	Execute an update query by a fixed batch size.
static <T> List<T>	list(Query query)
static <S extends Comparable<S>, T> List<T>	listByBatch(Query query, String batchParam, Collection<S> list, int batchSize)
static <S extends Comparable<S>, T> List<T>	listByBatch(Query query, String batchParam, Collection<S> list, int batchSize, int maxResults)	List the results of a query by a fixed batch size.
static <S extends Identifiable, T> List<T>	listByIdentifiableBatch(Query query, String batchParam, Collection<S> list, int batchSize)
static <S extends Identifiable, T> List<T>	listByIdentifiableBatch(Query query, String batchParam, Collection<S> list, int batchSize, int maxResults)
static <T extends Identifiable> Collection<T>	optimizeIdentifiableParameterList(Collection<T> list)	Optimize a collection of Identifiable entities.
static <T extends Comparable<T>> Collection<T>	optimizeParameterList(Collection<T> list)	Optimize a given parameter list by sorting, removing duplicates and padding to the next power of two.
static <T> Stream<T>	stream(Criteria criteria, Class<T> resultType, int fetchSize, boolean useCursorFetchIfSupported, boolean isQueryStateless)
static <T> Stream<T>	stream(Query query, Class<T> resultType, int fetchSize, boolean useCursorFetchIfSupported, boolean isQueryStateless)	Stream the result of a query with the given fetch size.
static <S extends Comparable<S>, T> Stream<T>	streamByBatch(Query query, String batchParam, Collection<S> list, int batchSize)	Stream the results of a query by a fixed batch size.
static <S extends Comparable<S>, T> Stream<T>	streamByBatch(Query query, String batchParam, Collection<S> list, int batchSize, Class<T> clazz)
static <T> T	uniqueResult(Query query)

Methods inherited from class Object

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

Field Details

MAX_PARAMETER_LIST_SIZE

public static final int MAX_PARAMETER_LIST_SIZE

Largest parameter list size for which optimizeParameterList(Collection) should be used. Past this size, no padding will be performed and a warning will be emitted.

See Also:

• Constant Field Values

Constructor Details

QueryUtils

public QueryUtils()

Method Details

list

public static <T> List<T> list(Query query)

See Also:

• Query.list()

uniqueResult

public static <T> T uniqueResult(Query query)

See Also:

• Query.uniqueResult()

optimizeParameterList

public static <T extends Comparable<T>>
Collection<T> optimizeParameterList(Collection<T> list)

Optimize a given parameter list by sorting, removing duplicates and padding to the next power of two.

This is a temporary solution until we update to Hibernate 5.2.18 which introduced hibernate.query.in_clause_parameter_padding. Read more about this topic.

optimizeIdentifiableParameterList

public static <T extends Identifiable>
Collection<T> optimizeIdentifiableParameterList(Collection<T> list)

Optimize a collection of Identifiable entities.

See Also:

• optimizeParameterList(Collection)

batchParameterList

public static <T extends Comparable<T>>
List<List<T>> batchParameterList(Collection<T> list,
 int batchSize)

Partition a parameter list into a collection of batches of a given size.

It is recommended to use a power of two in case the same query is also prepared via optimizeParameterList(Collection). This will make it so that the execution plan can be reused.

batchIdentifiableParameterList

public static <T extends Identifiable>
List<List<T>> batchIdentifiableParameterList(Collection<T> list,
 int batchSize)

listByBatch

public static <S extends Comparable<S>, T> List<T> listByBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize)

See Also:

• listByBatch(Query, String, Collection, int, int)

listByBatch

public static <S extends Comparable<S>, T> List<T> listByBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize,
 int maxResults)

List the results of a query by a fixed batch size.

Parameters:

query - the query

batchParam - a parameter of the query for batching

list - a collection of values for the batch parameters to retrieve

batchSize - the number of elements to fetch in each batch

maxResults - maximum number of results to return, or -1 to ignore

listByIdentifiableBatch

public static <S extends Identifiable, T> List<T> listByIdentifiableBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize)

listByIdentifiableBatch

public static <S extends Identifiable, T> List<T> listByIdentifiableBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize,
 int maxResults)

streamByBatch

public static <S extends Comparable<S>, T>
Stream<T> streamByBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize,
 Class<T> clazz)

See Also:

• streamByBatch(Query, String, Collection, int)

streamByBatch

public static <S extends Comparable<S>, T>
Stream<T> streamByBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize)

Stream the results of a query by a fixed batch size.

See Also:

• listByBatch(Query, String, Collection, int)

stream

public static <T> Stream<T> stream(Query query,
 Class<T> resultType,
 int fetchSize,
 boolean useCursorFetchIfSupported,
 boolean isQueryStateless)

Stream the result of a query with the given fetch size.

If it is determined that setFetchSize() will not work, a strategy based on offset/limit will be used.

Parameters:

useCursorFetchIfSupported - if cursor fetching is supported by the JDBC driver, it will be used. This has implications on performance of the database server because the whole result set will be loaded in memory

isQueryStateless - indicate if the query is stateless. A stateless query does not trigger any additional SQL statements upon being retrieved. If this is true, streaming will be enabled if useCursorFetchIfSupported is set to false.

stream

public static <T> Stream<T> stream(Criteria criteria,
 Class<T> resultType,
 int fetchSize,
 boolean useCursorFetchIfSupported,
 boolean isQueryStateless)

createStream

public static <T> Stream<T> createStream(SessionFactory sessionFactory,
 Function<Session, Stream<T>> streamFactory,
 boolean createNewSession)

Safely create a Stream from either the current or a new Session.

Parameters:

streamFactory - a function that produces the stream from a given Session. It may return null, in which case the session will be closed immediately

executeUpdateByBatch

public static <S extends Comparable<S>> int executeUpdateByBatch(Query query,
 String batchParam,
 Collection<S> list,
 int batchSize)

Execute an update query by a fixed batch size.

Returns:

the sum of all performed update executions

See Also:

• Query.executeUpdate()

escapeLike

public static String escapeLike(String s)