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HHH-14310 Document hibernate.query.in_clause_parameter_padding and some other missing config properties

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Christian Beikov 2020-11-10 16:56:11 +01:00 committed by Sanne Grinovero
parent 8e8844d485
commit ed3feeacad
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documentation/src/main/asciidoc/userguide/appendices/Configurations.adoc
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@ -275,6 +275,14 @@ Please report your mapping that causes the problem to us so we can examine the d
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The default value is `false` which means Hibernate will use an algorithm to determine if the insert can be delayed or if the insert should be performed immediately.
`*hibernate.id.sequence.increment_size_mismatch_strategy*` (e.g. `LOG`, `FIX` or `EXCEPTION` (default value))::
This setting defines the `org.hibernate.id.SequenceMismatchStrategy` used when
Hibernate detects a mismatch between a sequence configuration in an entity mapping
and its database sequence object counterpart.
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The default value is given by the `org.hibernate.id.SequenceMismatchStrategy#EXCEPTION`,
meaning that an Exception is thrown when detecting such a conflict.
==== Quoting options
`*hibernate.globally_quoted_identifiers*` (e.g. `true` or `false` (default value))::
@ -511,6 +519,30 @@ Raises an exception when in-memory pagination over collection fetch is about to
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Disabled by default. Set to true to enable.
`*hibernate.query.immutable_entity_update_query_handling_mode*` (e.g. `EXCEPTION` or `WARNING` (default value))::
Defines how `Immutable` entities are handled when executing a bulk update query.
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By default, the (`ImmutableEntityUpdateQueryHandlingMode#WARNING`) mode is used, meaning that
a warning log message is issued when an `@Immutable` entity is to be updated via a bulk update statement.
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If the (`ImmutableEntityUpdateQueryHandlingMode#EXCEPTION`) mode is used, then a `HibernateException` is thrown instead.
`*hibernate.query.in_clause_parameter_padding*` (e.g. `true` or `false` (default value))::
By default, the IN clause expands to include all bind parameter values.
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However, for database systems supporting execution plan caching,
there's a better chance of hitting the cache if the number of possible IN clause parameters lowers.
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For this reason, we can expand the bind parameters to power-of-two: 4, 8, 16, 32, 64.
This way, an IN clause with 5, 6, or 7 bind parameters will use the 8 IN clause,
therefore reusing its execution plan.
`*hibernate.query.omit_join_of_superclass_tables*` (e.g. `false` or `true` (default value))::
When you use `javax.persistence.InheritanceType#JOINED` strategy for inheritance mapping and query
a value from an entity, all superclass tables are joined in the query regardless you need them.
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With this setting set to true only superclass tables which are really needed are joined.
==== Multi-table bulk HQL operations
`*hibernate.hql.bulk_id_strategy*` (e.g. A fully-qualified class name, an instance, or a `Class` object reference)::