# How can I make Hibernate ignore my custom index?

**URL:** <https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149>\
**Category:** Hibernate ORM\
**Created:** [March 15, 2022, 5:14pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149 "2022-03-15T17:14:15Z")\
**Posts on this page:** 15\
**Page:** 1

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 15, 2022, 5:14pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/1 "2022-03-15T17:14:15Z")

</div>

In my Spring Boot 2.6.4 application (using Hibernate 5.6.5), I need to create a custom function-based MySQL 8 unique index to fulfil a database constraint. Since JPA doesn’t support defining function-based indexes, I have to create that index manually. But as soon as I create the index, the Hibernate schema migrator fails at startup, since it doesn’t expect an index to have index columns which have NULL names. For function-based indexes, MySQL returns the index metadata as using NULL as the column name if an expression is used, because then the expression is stored and returned separately. In my case, the index consists of two parts, one table column and one expression, so Hibernate sees the table column as the first column name and NULL as the second column name.

I create the index like this:

`create unique index custom_nonpublished ON articles (account_id,(case when status='PUBLISHED' then null else 'x' end));`

(the idea here is to enforce on database level that an account may have any number of articles in status PUBLISHED but at most one in another status)

In the MySQL client, “show keys from articles;” shows this for the index:

```auto
+----------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+---------------------------------------------------------------------------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | Visible | Expression |
+----------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+---------------------------------------------------------------------------------+
| articles | 0 | custom_nonpublished | 1 | account_id | A | 0 | NULL | NULL | | BTREE | | | YES | NULL |
| articles | 0 | custom_nonpublished | 2 | NULL | A | 0 | NULL | NULL | YES | BTREE | | | YES | (case when (`status` = _utf8mb4\'PUBLISHED\') then NULL else _utf8mb4\'x\' end) |
+----------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+---------------------------------------------------------------------------------+

```

How can I make Hibernate ignore my index when doing the schema migration? At first glance, I did not find a suitable way to patch anything (like InformationExtractorJdbcDatabaseMetaDataImpl or DatabaseMetaDataUsingInfoSchema) to ignore my index. Also, SchemaFilter does not support filtering out indexes.

Any hints are welcome.

The exception I get at startup is this:

```auto
Caused by: java.lang.IllegalArgumentException: null was passed as an object name
	at org.hibernate.engine.jdbc.env.internal.NormalizingIdentifierHelperImpl.toMetaDataObjectName(NormalizingIdentifierHelperImpl.java:196) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.extract.internal.TableInformationImpl.getColumn(TableInformationImpl.java:75) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.extract.internal.AbstractInformationExtractorImpl.lambda$getIndexes$8(AbstractInformationExtractorImpl.java:1149) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processIndexInfoResultSet(InformationExtractorJdbcDatabaseMetaDataImpl.java:118) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.extract.internal.AbstractInformationExtractorImpl.getIndexes(AbstractInformationExtractorImpl.java:1125) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.extract.internal.TableInformationImpl.indexes(TableInformationImpl.java:122) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.extract.internal.TableInformationImpl.getIndex(TableInformationImpl.java:138) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.findMatchingIndex(AbstractSchemaMigrator.java:361) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.applyIndexes(AbstractSchemaMigrator.java:345) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.internal.GroupedSchemaMigratorImpl.performTablesMigration(GroupedSchemaMigratorImpl.java:88) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.performMigration(AbstractSchemaMigrator.java:220) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.doMigration(AbstractSchemaMigrator.java:123) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:192) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.process(SchemaManagementToolCoordinator.java:81) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:335) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:471) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1498) ~[hibernate-core-5.6.5.Final.jar:5.6.5.Final]
	at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58) ~[spring-orm-5.3.16.jar:5.3.16]
	at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.3.16.jar:5.3.16]
	at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:409) ~[spring-orm-5.3.16.jar:5.3.16]
	... 128 common frames omitted

```

---

<div class="post-metadata">

**Author:** ![beikov](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/beikov/32/258_2.png) [@beikov](https://discourse.hibernate.org/u/beikov)\
**Post date:** [March 16, 2022, 8:47am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/2 "2022-03-16T08:47:52Z")

</div>

Looks like a bug. You should report that in the [issue tracker](https://hibernate.atlassian.net) and if it is important to you to get a fix soon, provide a PR with a fix for this.

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 16, 2022, 11:22am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/3 "2022-03-16T11:22:27Z")

</div>

I have created a bug in the issue tracker: [[HHH-15123] - Hibernate JIRA](https://hibernate.atlassian.net/browse/HHH-15123)

Before this is fixed in Hibernate itself, I would be interested to know if I have any means of customizing/configuring Hibernate to help me out.

---

<div class="post-metadata">

**Author:** ![beikov](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/beikov/32/258_2.png) [@beikov](https://discourse.hibernate.org/u/beikov)\
**Post date:** [March 16, 2022, 11:39am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/4 "2022-03-16T11:39:57Z")

</div>

You could register a custom `org.hibernate.tool.schema.spi.SchemaManagementTool` in a `org.hibernate.service.spi.ServiceContributor` which essentially allows you to change the `InformationExtractor` and skip these indexes.

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 16, 2022, 12:03pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/5 "2022-03-16T12:03:20Z")

</div>

OK, I will give this a try.

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 16, 2022, 3:57pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/6 "2022-03-16T15:57:53Z")

</div>

I’m trying to extend HibernateSchemaManagementTool, but I have trouble with the dependency injection. The method injectServices() is not called.

I’m using a ServiceContributor, which is registered in the file META-INF/services/org.hibernate.service.spi.ServiceContributor. My ServiceContributor is called and I register the service, like this:

```auto
    @Override
    public void contribute(StandardServiceRegistryBuilder serviceRegistryBuilder) {
        serviceRegistryBuilder.addService(SchemaManagementTool.class, new MySchemaManagementTool());
    }

```

This fails later since injectServices() is not called and therefore the parent’s serviceRegistry stays null. The parent implements ServiceRegistryAwareService. I can see that my child class is instantiated.

What am I missing? Why is injectServices() on the parent not called? I can see that it is called when my ServiceContributor is not used. According to the integration documentation, it should be enough to to implement the contribute() method to add the service, and it should then be configured automatically by calling injectServices() if it implements ServiceRegistryAwareService.

With the default implementation, I see

```auto
Initializing service [role=org.hibernate.tool.schema.spi.SchemaManagementTool]

```

and this is where injectServices() is called.

With my implementation, no such line is logged.

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 16, 2022, 4:46pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/7 "2022-03-16T16:46:30Z")

</div>

I’ve got it working now. I need to write my own version of a StandardServiceInitiator and need to use

`serviceRegistryBuilder.addInitiator(MySchemaManagementTool.INSTANCE);`

Maybe the integration guide should be updated accordingly.

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 17, 2022, 8:46am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/8 "2022-03-17T08:46:37Z")

</div>

I’ve patched getIndexes() to ignore indexes with NULL columns (changes are commented with “ADDED:”):

```auto
        @Override
        // copied from AbstractInformationExtractorImpl.getIndexes()
        public Iterable<IndexInformation> getIndexes(TableInformation tableInformation) {
            final Map<Identifier, IndexInformationImpl.Builder> builders = new HashMap<>();
            final QualifiedTableName tableName = tableInformation.getName();
            final Identifier catalog = tableName.getCatalogName();
            final Identifier schema = tableName.getSchemaName();

            final String catalogFilter;
            final String schemaFilter;

            if (catalog == null) {
                catalogFilter = "";
            } else {
                catalogFilter = catalog.getText();
            }

            if (schema == null) {
                schemaFilter = "";
            } else {
                schemaFilter = schema.getText();
            }

            try {
                processIndexInfoResultSet(catalogFilter, schemaFilter, tableName.getTableName().getText(), false, // DO NOT limit to just unique
                        true, // DO require up-to-date results
                        resultSet -> {
                            // ADDED: set
                            Set<Identifier> skipped = new HashSet<>();

                            while (resultSet.next()) {
                                if (resultSet.getShort(getResultSetIndexTypeLabel()) == DatabaseMetaData.tableIndexStatistic) {
                                    continue;
                                }

                                final Identifier indexIdentifier = DatabaseIdentifier.toIdentifier(resultSet.getString(getResultSetIndexNameLabel()));

                                // ADDED: if block
                                if (skipped.contains(indexIdentifier)) {
                                    continue;
                                }

                                IndexInformationImpl.Builder builder = builders.get(indexIdentifier);
                                if (builder == null) {
                                    builder = IndexInformationImpl.builder(indexIdentifier);
                                    builders.put(indexIdentifier, builder);
                                }

                                final Identifier columnIdentifier = DatabaseIdentifier
                                        .toIdentifier(resultSet.getString(getResultSetColumnNameLabel()));

                                // ADDED: if block
                                if (columnIdentifier == null) {
                                    // we've found an undefined index column name, probably due to a function-based index
                                    // skip the whole index
                                    builders.remove(indexIdentifier);
                                    // make sure it is not added again if another normal index column follows
                                    skipped.add(indexIdentifier);
                                    continue;
                                }

                                final ColumnInformation columnInformation = tableInformation.getColumn(columnIdentifier);
                                if (columnInformation == null) {
                                    // See HHH-10191: this may happen when dealing with Oracle/PostgreSQL function indexes
                                    LOG.logCannotLocateIndexColumnInformation(columnIdentifier.getText(), indexIdentifier.getText());
                                }
                                builder.addColumn(columnInformation);
                            }
                            return null;
                        });

            } catch (SQLException e) {
                throw convertSQLException(e, "Error accessing index information: " + tableInformation.getName().toString());
            }

            final List<IndexInformation> indexes = new ArrayList<>();
            for (IndexInformationImpl.Builder builder : builders.values()) {
                IndexInformationImpl index = builder.build();
                indexes.add(index);
            }
            return indexes;
        }
    }

```

Of course it would have been easier if the Lambda expression would have been externalized into a method instead.

---

<div class="post-metadata">

**Author:** ![beikov](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/beikov/32/258_2.png) [@beikov](https://discourse.hibernate.org/u/beikov)\
**Post date:** [March 17, 2022, 11:10am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/9 "2022-03-17T11:10:38Z")

</div>

Sorry for the trouble you ran into. I hope you can contribute the fixes back though!

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [March 17, 2022, 11:22am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/10 "2022-03-17T11:22:31Z")

</div>

My fix works with MySQL 8 (and probably also MariaDB). However, I don’t know how other databases (Oracle, SQLServer, PostgreSQL) would return index columns if a function-based index is used.

I’ve added a comment into [[HHH-15123] - Hibernate JIRA](https://hibernate.atlassian.net/browse/HHH-15123) regarding the possible fix above.

---

<div class="post-metadata">

**Author:** ![beikov](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/beikov/32/258_2.png) [@beikov](https://discourse.hibernate.org/u/beikov)\
**Post date:** [March 17, 2022, 3:30pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/11 "2022-03-17T15:30:02Z")

</div>

You could try to create a test similar to `org.hibernate.orm.test.dialect.functional.SQLServerDialectTempTableCollationTest` which creates the index on startup and drops it before shutdown.

---

<div class="post-metadata">

**Author:** ![Muddassir\_Rahman](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/muddassir_rahman/32/1984_2.png) [@Muddassir\_Rahman](https://discourse.hibernate.org/u/Muddassir_Rahman)\
**Post date:** [August 1, 2022, 7:06pm UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/12 "2022-08-01T19:06:42Z")

</div>

> [@ThomasSchuerger](#):
>
> `SchemaManagementTool`

Can you post the complete class of this .?

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [August 2, 2022, 8:38am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/13 "2022-08-02T08:38:24Z")

</div>

See my solution here. The actual code changes in the getIndexes() method are marked using “// ADDED:”.

Add a new class HibernateServiceContributor:

```auto
package mypackage.config;

import java.io.Serializable;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.hibernate.boot.model.naming.DatabaseIdentifier;
import org.hibernate.boot.model.naming.Identifier;
import org.hibernate.boot.model.relational.QualifiedTableName;
import org.hibernate.boot.model.relational.SqlStringGenerationContext;
import org.hibernate.boot.registry.StandardServiceInitiator;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.boot.registry.selector.spi.StrategySelector;
import org.hibernate.cfg.AvailableSettings;
import org.hibernate.engine.jdbc.env.spi.JdbcEnvironment;
import org.hibernate.resource.transaction.spi.DdlTransactionIsolator;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.spi.ServiceContributor;
import org.hibernate.service.spi.ServiceRegistryAwareService;
import org.hibernate.service.spi.ServiceRegistryImplementor;
import org.hibernate.tool.schema.extract.internal.IndexInformationImpl;
import org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl;
import org.hibernate.tool.schema.extract.spi.ColumnInformation;
import org.hibernate.tool.schema.extract.spi.ExtractionContext;
import org.hibernate.tool.schema.extract.spi.IndexInformation;
import org.hibernate.tool.schema.extract.spi.InformationExtractor;
import org.hibernate.tool.schema.extract.spi.TableInformation;
import org.hibernate.tool.schema.internal.HibernateSchemaManagementTool;
import org.hibernate.tool.schema.internal.exec.ImprovedExtractionContextImpl;
import org.hibernate.tool.schema.spi.ExtractionTool;
import org.hibernate.tool.schema.spi.SchemaManagementTool;

import lombok.extern.slf4j.Slf4j;

/**
 * Customizes Hibernate to ignore function-based indexes when extracting schema metadata for the schema migration. This is necessary, because
 * otherwise the Hibernate schema migrator runs into a fatal error since it cannot handle indexes with NULL columns (which is the case if an FBI uses
 * an expression as an index column). See https://hibernate.atlassian.net/browse/HHH-15123.
 *
 * @author Thomas Schuerger (thomas@schuerger.com)
 */

@Slf4j
public class HibernateServiceContributor extends HibernateSchemaManagementTool implements ServiceContributor {

    private static final long serialVersionUID = 1L;

    @Override
    public void contribute(StandardServiceRegistryBuilder serviceRegistryBuilder) {
        serviceRegistryBuilder.addInitiator(MySchemaManagementToolInitiator.INSTANCE);
    }

    // copied from SchemaManagementToolInitiator
    public static class MySchemaManagementToolInitiator implements StandardServiceInitiator<SchemaManagementTool> {
        public static final MySchemaManagementToolInitiator INSTANCE = new MySchemaManagementToolInitiator();

        @Override
        public SchemaManagementTool initiateService(Map configurationValues, ServiceRegistryImplementor registry) {
            final Object setting = configurationValues.get(AvailableSettings.SCHEMA_MANAGEMENT_TOOL);
            SchemaManagementTool tool = registry.getService(StrategySelector.class).resolveStrategy(SchemaManagementTool.class, setting);
            if (tool == null) {
                tool = new MySchemaManagementTool();
            }

            return tool;
        }

        @Override
        public Class<SchemaManagementTool> getServiceInitiated() {
            return SchemaManagementTool.class;
        }
    }

    public static class MySchemaManagementTool extends HibernateSchemaManagementTool implements ServiceRegistryAwareService {
        private static final long serialVersionUID = 6524723430296138443L;

        private ExtractionTool extractionTool = new MyExtractionTool();

        @Override
        public ExtractionTool getExtractionTool() {
            return extractionTool;
        }
    }

    // copied from the private class HibernateSchemaManagementTool.HibernateExtractionTool
    public static class MyExtractionTool implements ExtractionTool, Serializable {
        private static final long serialVersionUID = -5281243360224393715L;

        @Override
        public ExtractionContext createExtractionContext(ServiceRegistry serviceRegistry, JdbcEnvironment jdbcEnvironment,
                SqlStringGenerationContext sqlStringGenerationContext, DdlTransactionIsolator ddlTransactionIsolator,
                ExtractionContext.DatabaseObjectAccess databaseObjectAccess) {
            return new ImprovedExtractionContextImpl(serviceRegistry, jdbcEnvironment, sqlStringGenerationContext, ddlTransactionIsolator,
                    databaseObjectAccess);
        }

        @Override
        public InformationExtractor createInformationExtractor(ExtractionContext extractionContext) {
            return new MyInformationExtractorJdbcDatabaseMetaDataImpl(extractionContext);
        }
    }

    public static class MyInformationExtractorJdbcDatabaseMetaDataImpl extends InformationExtractorJdbcDatabaseMetaDataImpl {

        public MyInformationExtractorJdbcDatabaseMetaDataImpl(ExtractionContext extractionContext) {
            super(extractionContext);
        }

        @Override
        // copied from AbstractInformationExtractorImpl.getIndexes()
        public Iterable<IndexInformation> getIndexes(TableInformation tableInformation) {
            final Map<Identifier, IndexInformationImpl.Builder> builders = new HashMap<>();
            final QualifiedTableName tableName = tableInformation.getName();
            final Identifier catalog = tableName.getCatalogName();
            final Identifier schema = tableName.getSchemaName();

            final String catalogFilter;
            final String schemaFilter;

            if (catalog == null) {
                catalogFilter = "";
            } else {
                catalogFilter = catalog.getText();
            }

            if (schema == null) {
                schemaFilter = "";
            } else {
                schemaFilter = schema.getText();
            }

            try {
                processIndexInfoResultSet(catalogFilter, schemaFilter, tableName.getTableName().getText(), false, // DO NOT limit to just unique
                        true, // DO require up-to-date results
                        resultSet -> {
                            // ADDED: set
                            Set<Identifier> skipped = new HashSet<>();

                            while (resultSet.next()) {
                                if (resultSet.getShort(getResultSetIndexTypeLabel()) == DatabaseMetaData.tableIndexStatistic) {
                                    continue;
                                }

                                final Identifier indexIdentifier = DatabaseIdentifier.toIdentifier(resultSet.getString(getResultSetIndexNameLabel()));

                                // ADDED: if block
                                if (skipped.contains(indexIdentifier)) {
                                    continue;
                                }

                                IndexInformationImpl.Builder builder = builders.get(indexIdentifier);
                                if (builder == null) {
                                    builder = IndexInformationImpl.builder(indexIdentifier);
                                    builders.put(indexIdentifier, builder);
                                }

                                final Identifier columnIdentifier = DatabaseIdentifier
                                        .toIdentifier(resultSet.getString(getResultSetColumnNameLabel()));

                                // ADDED: if block
                                if (columnIdentifier == null) {
                                    // we've found an undefined index column name, probably due to a function-based index
                                    // skip the whole index
                                    LOG.info("Skipping function-based index " + tableName + "." + indexIdentifier + " for schema migration");
                                    builders.remove(indexIdentifier);
                                    // make sure it is not added again if another normal index column follows
                                    skipped.add(indexIdentifier);
                                    continue;
                                }

                                final ColumnInformation columnInformation = tableInformation.getColumn(columnIdentifier);
                                builder.addColumn(columnInformation);
                            }
                            return null;
                        });

            } catch (SQLException e) {
                throw convertSQLException(e, "Error accessing index information: " + tableInformation.getName().toString());
            }

            final List<IndexInformation> indexes = new ArrayList<>();
            for (IndexInformationImpl.Builder builder : builders.values()) {
                IndexInformationImpl index = builder.build();
                indexes.add(index);
            }
            return indexes;
        }
    }
}

```

Then I added the file META-INF/services/org.hibernate.service.spi.ServiceContributor to the application with the FQCN of that class:

```auto
mypackage.config.HibernateServiceContributor

```

---

<div class="post-metadata">

**Author:** ![ThomasSchuerger](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/thomasschuerger/32/1829_2.png) [@ThomasSchuerger](https://discourse.hibernate.org/u/ThomasSchuerger)\
**Post date:** [August 2, 2022, 8:40am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/15 "2022-08-02T08:40:35Z")

</div>

I’ve posted the solution. Hope it helps!

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<div class="post-metadata">

**Author:** ![Muddassir\_Rahman](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/muddassir_rahman/32/1984_2.png) [@Muddassir\_Rahman](https://discourse.hibernate.org/u/Muddassir_Rahman)\
**Post date:** [August 2, 2022, 10:48am UTC](https://discourse.hibernate.org/t/how-can-i-make-hibernate-ignore-my-custom-index/6149/16 "2022-08-02T10:48:49Z")

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@ThomasSchuerger Thank you so much ! It was life saving 🙂