Package org.hibernate.dialect.function.array

Class H2UnnestFunction

java.lang.Object

org.hibernate.query.sqm.function.AbstractSqmSetReturningFunctionDescriptor

org.hibernate.query.sqm.function.AbstractSqmSelfRenderingSetReturningFunctionDescriptor

org.hibernate.dialect.function.array.UnnestFunction

org.hibernate.dialect.function.array.H2UnnestFunction

All Implemented Interfaces:

SetReturningFunctionRenderer, SqmSetReturningFunctionDescriptor

public class H2UnnestFunction
extends UnnestFunction

H2 unnest function.

H2 does not support "lateral" i.e. the use of a from node within another, but we can apply the same trick that we already applied everywhere else for H2, which is to join a sequence table to emulate array element rows and eliminate non-existing array elements by checking the index against array length. Finally, we rewrite the selection expressions to access the array by joined sequence index.

Constructor Summary

Constructors

Constructor	Description
H2UnnestFunction(int maximumArraySize)

Method Summary

Modifier and Type	Method	Description
protected <T> SelfRenderingSqmSetReturningFunction<T>	generateSqmSetReturningFunctionExpression(List<? extends SqmTypedNode<?>> arguments, QueryEngine queryEngine)	Return an SQM node or subtree representing an invocation of this function with the given arguments.
protected void	renderJsonTable(SqlAppender sqlAppender, Expression array, BasicPluralType<?,?> pluralType, @Nullable SqlTypedMapping sqlTypedMapping, AnonymousTupleTableGroupProducer tupleType, String tableIdentifierVariable, SqlAstTranslator<?> walker)
protected void	renderUnnest(SqlAppender sqlAppender, Expression array, BasicPluralType<?,?> pluralType, @Nullable SqlTypedMapping sqlTypedMapping, AnonymousTupleTableGroupProducer tupleType, String tableIdentifierVariable, SqlAstTranslator<?> walker)

Methods inherited from class org.hibernate.dialect.function.array.UnnestFunction

getDdlType, render, renderJsonTableColumns, renderXmlTable, renderXmlTableColumns

Methods inherited from class org.hibernate.query.sqm.function.AbstractSqmSetReturningFunctionDescriptor

generateSqmExpression, getArgumentListSignature, getArgumentsValidator, getArgumentTypeResolver, getName, getSetReturningTypeResolver, getSignature

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.hibernate.query.sqm.function.SetReturningFunctionRenderer

rendersIdentifierVariable

Constructor Details

H2UnnestFunction

public H2UnnestFunction(int maximumArraySize)

Method Details

generateSqmSetReturningFunctionExpression

protected <T>
SelfRenderingSqmSetReturningFunction<T> generateSqmSetReturningFunctionExpression(List<? extends SqmTypedNode<?>> arguments,
 QueryEngine queryEngine)

Description copied from class: AbstractSqmSetReturningFunctionDescriptor

Return an SQM node or subtree representing an invocation of this function with the given arguments. This method may be overridden in the case of function descriptors that wish to customize creation of the node.

Overrides:

generateSqmSetReturningFunctionExpression in class AbstractSqmSelfRenderingSetReturningFunctionDescriptor

Parameters:

arguments - the arguments of the function invocation

renderJsonTable

protected void renderJsonTable(SqlAppender sqlAppender,
 Expression array,
 BasicPluralType<?,?> pluralType,
 @Nullable SqlTypedMapping sqlTypedMapping,
 AnonymousTupleTableGroupProducer tupleType,
 String tableIdentifierVariable,
 SqlAstTranslator<?> walker)

Overrides:

renderJsonTable in class UnnestFunction

renderUnnest

protected void renderUnnest(SqlAppender sqlAppender,
 Expression array,
 BasicPluralType<?,?> pluralType,
 @Nullable SqlTypedMapping sqlTypedMapping,
 AnonymousTupleTableGroupProducer tupleType,
 String tableIdentifierVariable,
 SqlAstTranslator<?> walker)

Overrides:

renderUnnest in class UnnestFunction