# diffChangeLog is generating redundant modifyDataType changes

**URL:** <https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032>\
**Category:** General Discussion\
**Created:** [April 7, 2023, 12:47pm UTC](https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032 "2023-04-07T12:47:01Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![adamcc](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.liquibase.org/adamcc/32/964_2.png) [@adamcc](https://forum.liquibase.org/u/adamcc)\
**Post date:** [April 7, 2023, 12:47pm UTC](https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032/1 "2023-04-07T12:47:01Z")

</div>

Hi,

Context:

- I have a Spring Boot project running off PostgreSQL.
- My entities are defined using JPA annotations
- I integrated Liquibase 4.20 in my gradle build using the plugin `org.liquibase.gradle`
- I use `generateChangeLog` task to create the initial changelog, which I put in `src/main/resources/db/changelog`
- I use gradle plugin `docker-compose` to start a new docker container running PostgreSQL
- I use the existing changeset in `src/main/resources/db/changelog`, to get the current schema in to the new PostgreSQL instance
- I run `diffChangeLog` task, to compare the JPA Entities in my source code with the fresh installed schema in PostgreSQL, and generate a diff changelog.

**I would expect this diffChangeLog to be empty** , because my entities have not changed since I generated the changeset in `src/main/resources/db/changelog`. Instead it generates a change for some of the columns in the schema, with an unnecessary modifyDataType operation.

> **JPA Entity: OrderAddressEntity.java**
>
> ```auto
> package com.acroteq.order.service.data.access.order.entity;
> 
> import jakarta.persistence.Entity;
> import jakarta.persistence.Id;
> import jakarta.persistence.JoinColumn;
> import jakarta.persistence.OneToOne;
> import jakarta.persistence.Table;
> import lombok.EqualsAndHashCode;
> import lombok.Getter;
> import lombok.NoArgsConstructor;
> import lombok.Setter;
> 
> import java.util.UUID;
> 
> import static jakarta.persistence.CascadeType.ALL;
> 
> @Getter
> @Setter
> @NoArgsConstructor
> @EqualsAndHashCode(onlyExplicitlyIncluded = true)
> @Table(name = "order_addresses")
> @Entity
> public class OrderAddressEntity {
> 
> @EqualsAndHashCode.Include
> @Id
> private UUID id;
> 
> @OneToOne(cascade = ALL)
> @JoinColumn(name="order_id")
> private OrderEntity order;
> 
> private String street;
> 
> private String postalCode;
> 
> private String city;
> }
> 
> ```

> **Original changeset, generated from JPA entities using \`generateChangeLog\`**
>
> ```auto
> databaseChangeLog:
> - changeSet:
> id: 1680856586804-2
> author: adamcc (generated)
> changes:
> - createTable:
> columns:
> - column:
> constraints:
> nullable: false
> primaryKey: true
> primaryKeyName: order_addressesPK
> name: id
> type: BYTEA
> - column:
> name: city
> type: VARCHAR(255)
> - column:
> name: postalCode
> type: VARCHAR(255)
> - column:
> name: street
> type: VARCHAR(255)
> - column:
> name: order_id
> type: BYTEA
> tableName: order_addresses
> 
> ```

> **Generated PostgreSQL schema for table order\_addresses\`**
>
> ![2023-04-07_141204](https://us1.discourse-cdn.com/flex020/uploads/liquibase1/original/1X/f70377ba473b06cdf18fbb85a626e83db8975158.png)

> **Diff changeset, generated by comparing JPA entities to posgres schema, using \`diffChangeLog\`**
>
> ```auto
> databaseChangeLog:
> - changeSet:
> id: 1680867980582-1
> author: micro (generated)
> changes:
> - modifyDataType:
> columnName: city
> newDataType: varchar(255)
> tableName: order_addresses
> - changeSet:
> id: 1680867980582-5
> author: micro (generated)
> changes:
> - modifyDataType:
> columnName: postalCode
> newDataType: varchar(255)
> tableName: order_addresses
> - changeSet:
> id: 1680867980582-7
> author: micro (generated)
> changes:
> - modifyDataType:
> columnName: street
> newDataType: varchar(255)
> tableName: order_addresses
> 
> ```

As you can see, column “city” is data type “varchar(255)”, both in the original and the diff changesets, and also in the PostgreSQL schema. A modifyDataType change has been generated that does not change the type.

I have been trying to get this to work as expected for 2 days now, and I am stumped. I’m guessing that there is something missing or wrongly configured in a type map somewhere, and the `diffChangeLog` operation is reading different data types from postgreSQL than what is generated by the Hibernate dialect, so it is incorrectly identifying a change. It then generates a new change, and takes the changed data type from the JPA Entity, which is identical again.

Details of the build setup follow next.

I would appreciate any hints.

Thanks,

Adam

---

<div class="post-metadata">

**Author:** ![adamcc](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.liquibase.org/adamcc/32/964_2.png) [@adamcc](https://forum.liquibase.org/u/adamcc)\
**Post date:** [April 7, 2023, 12:47pm UTC](https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032/2 "2023-04-07T12:47:46Z")

</div>

Here’s the details of the build and the liquibase calls:

> **liquibase.gradle (includes the Liquibase activities)**
>
> ```auto
> apply plugin: 'org.liquibase.gradle'
> 
> configurations {
> liquibaseRuntime.extendsFrom compileClasspath
> }
> 
> dependencies {
> liquibaseRuntime libs.picocli
> liquibaseRuntime libs.snakeyaml
> liquibaseRuntime libs.liquibase.core
> liquibaseRuntime libs.liquibase.hibernate
> liquibaseRuntime libs.liquibase.groovy.dsl
> liquibaseRuntime libs.postgresql.driver
> liquibaseRuntime libs.spring.boot.data.jpa
> liquibaseRuntime sourceSets.main.output
> }
> 
> dockerCompose {
> useComposeFiles = ["docker-compose.yaml"]
> startedServices = ['postgres'] //, 'pgadmin']
> dockerComposeWorkingDirectory = projectDir
> }
> 
> composeUp {
> finalizedBy composeDown
> doLast {
> project.ext.set("postgresqlPort", dockerCompose.servicesInfos.postgres.ports[5432])
> }
> }
> 
> liquibaseDropAll {
> dependsOn composeUp
> finalizedBy composeDown
> 
> doFirst() {
> liquibase {
> jvmArgs "-Duser.dir=$projectDir"
> activities {
> dropSchema {
> url "jdbc:postgresql://localhost:${project.postgresqlPort}/postgres"
> driver "org.postgresql.Driver"
> username "postgres"
> password "password"
> logFile "build/liquibase/liquibase_dropall.log"
> logLevel "FINE"
> }
> runList = 'dropSchema'
> }
> }
> }
> }
> 
> liquibaseUpdate {
> // Start up postgres docker container before running liquibaseDiffChangelog and shut it down after
> dependsOn liquibaseDropAll
> dependsOn composeUp
> finalizedBy composeDown
> 
> doFirst() {
> liquibase {
> jvmArgs "-Duser.dir=$projectDir"
> activities {
> deployChangeLog {
> changelogFile "src/main/resources/db/changelog/changelog_master.yaml"
> url "jdbc:postgresql://localhost:${project.postgresqlPort}/postgres"
> driver "org.postgresql.Driver"
> username "postgres"
> password "password"
> logFile "build/liquibase/liquibase_update.log"
> logLevel "FINE"
> }
> runList = 'deployChangeLog'
> }
> }
> }
> }
> 
> liquibaseDiffChangelog {
> dependsOn liquibaseUpdate
> finalizedBy composeDown
> 
> doFirst() {
> liquibase {
> jvmArgs "-Duser.dir=$projectDir"
> activities {
> generateDiffChangeLog {
> changelogFile "./build/liquibase/changelog_diff.yaml"
> overwriteOutputFile true
> url "jdbc:postgresql://localhost:${project.postgresqlPort}/postgres"
> driver "org.postgresql.Driver"
> username "postgres"
> password "password"
> referenceUrl "hibernate:spring:com.acroteq.order.service.data.access?dialect=org.hibernate.dialect.PostgreSQLDialect&" +
> "hibernate.physical_naming_strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl&" +
> "hibernate.implicit_naming_strategy=org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy"
> referenceDriver "liquibase.ext.hibernate.database.connection.HibernateDriver"
> logFile "./build/liquibase/liquibase_diff.log"
> logLevel "FINE"
> }
> runList = 'generateDiffChangeLog'
> }
> }
> }
> }
> 
> liquibaseGenerateChangelog {
> dependsOn compileJava
> 
> doFirst() {
> liquibase {
> jvmArgs "-Duser.dir=$projectDir"
> activities {
> generateChangeLog {
> changelogFile "./build/liquibase/changelog.yaml"
> overwriteOutputFile true
> url "hibernate:spring:com.acroteq.order.service.data.access?dialect=org.hibernate.dialect.PostgreSQLDialect&" +
> "hibernate.physical_naming_strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl&"
> "hibernate.implicit_naming_strategy=org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy"
> driver "liquibase.ext.hibernate.database.connection.HibernateDriver"
> logFile "./build/liquibase/liquibase_gen.log"
> logLevel "FINE"
> }
> runList = 'generateChangeLog'
> }
> }
> }
> }
> 
> ```

> **liquibase.properties**
>
> ```auto
> liquibase.logLevel=fine
> liquibase.promptForNonLocalDatabase=true
> liquibase.showBanner=false
> liquibase.convertDataTypes=true
> liquibase.diffColumnOrder=false
> #liquibase.changelogParseMode=lax
> #liquibase.command.diffChangelog.format=yaml
> 
> ```

> **settings.gradle**
>
> ```auto
> dependencyResolutionManagement {
> versionCatalogs {
> libs {
> // Spring
> version('spring', '6.0.7')
> library('spring-core', 'org.springframework', 'spring-core').versionRef('spring')
> library('spring-beans', 'org.springframework', 'spring-beans').versionRef('spring')
> library('spring-context', 'org.springframework', 'spring-context').versionRef('spring')
> library('spring-tx', 'org.springframework', 'spring-tx').versionRef('spring')
> library('spring-test', 'org.springframework', 'spring-test').versionRef('spring')
> 
> // Spring Boot
> version('springBoot', '3.0.5')
> library('spring-boot-core', 'org.springframework.boot', 'spring-boot').versionRef('springBoot')
> library('spring-boot-autoconfigure', 'org.springframework.boot', 'spring-boot-autoconfigure').versionRef('springBoot')
> library('spring-boot-web', 'org.springframework.boot', 'spring-boot-starter-web').versionRef('springBoot')
> library('spring-boot-validation', 'org.springframework.boot', 'spring-boot-starter-validation').versionRef('springBoot')
> library('spring-boot-thymeleaf', 'org.springframework.boot', 'spring-boot-starter-thymeleaf').versionRef('springBoot')
> library('spring-boot-data-jpa', 'org.springframework.boot', 'spring-boot-starter-data-jpa').versionRef('springBoot')
> library('spring-boot-configuration-processor', 'org.springframework.boot', 'spring-boot-configuration-processor').versionRef('springBoot')
> library('spring-boot-test', 'org.springframework.boot', 'spring-boot-test').versionRef('springBoot')
> 
> // Postgres
> library('postgresql-driver', 'org.postgresql', 'postgresql').version('42.6.0')
> 
> // Liquibase
> version('liquibase', '4.20.0')
> library('picocli', 'info.picocli', 'picocli').version('4.7.1')
> library('snakeyaml', 'org.yaml', 'snakeyaml').version('2.0')
> library('liquibase-core', 'org.liquibase', 'liquibase-core').versionRef('liquibase')
> library('liquibase-hibernate', 'org.liquibase.ext', 'liquibase-hibernate6').versionRef('liquibase')
> library('liquibase-groovy-dsl', 'org.liquibase', 'liquibase-groovy-dsl').version('3.0.3')
> }
> 
> pluginLibs {
> plugin('liquibase', 'org.liquibase.gradle').version('2.2.0')
> plugin('docker-compose', 'com.avast.gradle.docker-compose').version('0.16.12')
> plugin('spring-boot', 'org.springframework.boot').version('3.0.5')
> }
> }
> }
> 
> ```

> **docker-compose.yaml**
>
> ```auto
> version: '3'
> services:
> postgres:
> image: postgres:15.2-alpine
> environment:
> POSTGRES_USER: postgres
> POSTGRES_PASSWORD: password
> POSTGRES_DB: postgres
> volumes:
> - ./build/postgresql:/var/lib/postgresql/data
> ports:
> - "5432"
> networks:
> - app-tier
> pgadmin:
> image: dpage/pgadmin4:2023-04-04-1
> environment:
> PGADMIN_DEFAULT_EMAIL: pgadmin@adamcc.ch
> PGADMIN_DEFAULT_PASSWORD: pgadmin
> PGADMIN_LISTEN_PORT: 5050
> ports:
> - 5050:5050
> networks:
> - app-tier
> networks:
> app-tier:
> driver: bridge
> 
> ```

---

<div class="post-metadata">

**Author:** ![adamcc](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.liquibase.org/adamcc/32/964_2.png) [@adamcc](https://forum.liquibase.org/u/adamcc)\
**Post date:** [April 7, 2023, 12:54pm UTC](https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032/5 "2023-04-07T12:54:35Z")

</div>

> **Log output from the \`diffChangeLog\` operation**
>
> ```auto
> [2023-04-07 14:53:16] INFO [liquibase.integration] Starting command execution.
> [2023-04-07 14:53:17] INFO [liquibase.ext] Reading hibernate configuration hibernate:spring:com.acroteq.food.ordering.system.order.service.data.access?dialect=org.hibernate.dialect.PostgreSQLDialect&hibernate.physical_naming_strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl&hibernate.implicit_naming_strategy=org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy
> [2023-04-07 14:53:17] INFO [liquibase.ext] Found package com.acroteq.food.ordering.system.order.service.data.access
> [2023-04-07 14:53:18] INFO [liquibase.ext] Using dialect org.hibernate.dialect.PostgreSQLDialect
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_addresses
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_addresses
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_items
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_items
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table orders
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table orders
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_items
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_items
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table OrderEntity_failureMessages
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table OrderEntity_failureMessages
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_items
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found primary key order_itemsPK
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column id bigint
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column productId bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column quantity integer
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column order_id bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column id bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table orders
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found primary key ordersPK
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column id bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column customerId bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column orderStatus varchar(255)
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column priceAmount numeric(38, 2)
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column priceCurrencyId bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column restaurantId bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column trackingId bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table order_addresses
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found primary key order_addressesPK
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column id bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column city varchar(255)
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column postalCode varchar(255)
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column street varchar(255)
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column order_id bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found table OrderEntity_failureMessages
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column OrderEntity_id bytea
> [2023-04-07 14:53:18] INFO [liquibase.ext] Found column failureMessages varchar(255)
> [2023-04-07 14:53:18] INFO [liquibase.database] Set default schema name to public
> [2023-04-07 14:53:18] INFO [liquibase.diff] changeSets count: 7
> [2023-04-07 14:53:18] INFO [liquibase.diff] ./build/liquibase/changelog_diff.yaml does not exist, creating and adding 7 changesets.
> [2023-04-07 14:53:18] WARNING [liquibase.resource] Failed to create parent directories for file build\liquibase\changelog_diff.yaml
> 
> ```

---

<div class="post-metadata">

**Author:** ![kotsy](https://avatars.discourse-cdn.com/v4/letter/k/ba9def/32.png) [@kotsy](https://forum.liquibase.org/u/kotsy)\
**Post date:** [April 10, 2023, 4:14pm UTC](https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032/6 "2023-04-10T16:14:11Z")

</div>

I don’t have the answer, but i wanted to let you know, that i have exact the same problem using “mvn liquibase:diff” in a maven spring boot solution using the latest liquibase 4.20 and hibernate6. in the changelog (.sql) it generates the following redundant column type changes for every property of the Entity:

ALTER TABLE users ALTER COLUMN username TYPE VARCHAR(255) USING (username::VARCHAR(255));

Even after applying this changelog using mvn liquibase:update this changes are generated again 😕

With version 4.19.0 of liquibase + maven plugin everythink works fine!

I think it’s a good idea to create an issue here: [Issues · liquibase/liquibase · GitHub](https://github.com/liquibase/liquibase/issues)

Here is an issue, describing the same problem:  
[Unnecessary ALTER TABLE statements for PostgreSQL 15 · Issue #4047 · liquibase/liquibase · GitHub](https://github.com/liquibase/liquibase/issues/4047)

---

<div class="post-metadata">

**Author:** ![adamcc](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.liquibase.org/adamcc/32/964_2.png) [@adamcc](https://forum.liquibase.org/u/adamcc)\
**Post date:** [April 11, 2023, 7:21am UTC](https://forum.liquibase.org/t/diffchangelog-is-generating-redundant-modifydatatype-changes/8032/7 "2023-04-11T07:21:34Z")

</div>

Turns out you do have the answer 🙂

This was my first Liquibase implementation (in this project), and I did not think to try a previous version. I rolled back to 4.19.0 as you suggested, and it works!

Thanks very much for the hint.

I will comment in the existing GitHub issue - I don’t thnk we need to make a new one.