Liquibase: how to load data with CURRENT_TIMESTAMP? - postgresql

Question

I am trying to update my project, going from
<liquibase.version>3.5.5</liquibase.version>
<liquibase-hibernate5.version>3.6</liquibase-hibernate5.version>
to
<liquibase.version>3.9.0</liquibase.version>
<liquibase-hibernate5.version>3.8</liquibase-hibernate5.version>
and I'm having some troubles while loading data from CSV files, which contain some columns having the current timestamp as value.
E.g my CSV file:
id;name;created;modified
1;Book A;now();now()
2;Book B;now();now()
The Book table is created with:
<createTable tableName="book">
<column name="id" type="bigint" autoIncrement="${autoIncrement}">
<constraints primaryKey="true" nullable="false"/>
</column>
<column name="name" type="varchar(255)">
<constraints nullable="false"/>
</column>
<column name="created" type="timestamp">
<constraints nullable="false"/>
</column>
<column name="modified" type="timestamp">
<constraints nullable="false"/>
</column>
</createTable>
And the data is loaded with:
<property name="now" value="current_timestamp" dbms="postgresql"/>
<changeSet id="20180508144233-1" author="developer">
<loadData catalogName="public"
encoding="UTF-8"
file="config/liquibase/books.csv"
schemaName="public"
separator=";"
quotchar="'"
tableName="book">
</loadData>
</changeSet>
With the previous version of Liquibase it was working fine, however after the update I am getting the following error:
2020-06-26 16:49:57 [project-Executor-1] [ERROR] liquibase.changelog.ChangeSet - Change Set config/liquibase/changelog/20180508144233_added_books_data.xml::20180508144233-1::developer failed. Error: liquibase.exception.DateParseException: Improper value in 'NOW' value: now(). 'NOW' must be followed by + or -, then numeric offset, then units (h{our{s}}, m{inute{s}}, d{ay{s}}, or y{ears}
Hibernate: select answerweig0_.id as id1_1_, answerweig0_.likelihood as likeliho2_1_, answerweig0_.question_type as question3_1_, answerweig0_.weight as weight4_1_ from answer_weight answerweig0_
2020-06-26 16:49:57 [project-Executor-1] [ERROR] i.g.j.c.l.AsyncSpringLiquibase - Liquibase could not start correctly, your database is NOT ready: Migration failed for change set config/liquibase/changelog/20180508144233_added_books_data.xml::20180508144233-1::developer:
Reason: liquibase.exception.UnexpectedLiquibaseException: liquibase.exception.DateParseException: Improper value in 'NOW' value: now(). 'NOW' must be followed by + or -, then numeric offset, then units (h{our{s}}, m{inute{s}}, d{ay{s}}, or y{ears}
liquibase.exception.MigrationFailedException: Migration failed for change set config/liquibase/changelog/20180508144233_added_books_data.xml::20180508144233-1::developer:
Reason: liquibase.exception.UnexpectedLiquibaseException: liquibase.exception.DateParseException: Improper value in 'NOW' value: now(). 'NOW' must be followed by + or -, then numeric offset, then units (h{our{s}}, m{inute{s}}, d{ay{s}}, or y{ears}
at liquibase.changelog.ChangeSet.execute(ChangeSet.java:646)
at liquibase.changelog.visitor.UpdateVisitor.visit(UpdateVisitor.java:53)
at liquibase.changelog.ChangeLogIterator.run(ChangeLogIterator.java:83)
at liquibase.Liquibase.update(Liquibase.java:202)
at liquibase.Liquibase.update(Liquibase.java:179)
at liquibase.integration.spring.SpringLiquibase.performUpdate(SpringLiquibase.java:366)
at liquibase.integration.spring.SpringLiquibase.afterPropertiesSet(SpringLiquibase.java:314)
at org.springframework.boot.autoconfigure.liquibase.DataSourceClosingSpringLiquibase.afterPropertiesSet(DataSourceClosingSpringLiquibase.java:46)
at io.github.jhipster.config.liquibase.AsyncSpringLiquibase.initDb(AsyncSpringLiquibase.java:118)
at io.github.jhipster.config.liquibase.AsyncSpringLiquibase.lambda$afterPropertiesSet$0(AsyncSpringLiquibase.java:93)
at io.github.jhipster.async.ExceptionHandlingAsyncTaskExecutor.lambda$createWrappedRunnable$1(ExceptionHandlingAsyncTaskExecutor.java:78)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

Answer 1

As a workaround, I was able to set the values for such columns by using a default value in the table creation changelog:
<createTable tableName="book">
<column name="id" type="bigint" autoIncrement="${autoIncrement}">
<constraints primaryKey="true" nullable="false"/>
</column>
<column name="name" type="varchar(255)">
<constraints nullable="false"/>
</column>
<column name="created" type="timestamp" defaultValueComputed="CURRENT_TIMESTAMP">
<constraints nullable="false"/>
</column>
<column name="modified" type="timestamp" defaultValueComputed="CURRENT_TIMESTAMP">
<constraints nullable="false"/>
</column>
</createTable>
and removing the corresponding columns from the CSV file:
id;name
1;Book A
2;Book B
However, I'm still looking for a way to keep the CURRENT_TIMESTAMP value in the CSV file.

Answer 2

Your workaround is pretty much correct. But depending on database you will have to add a way that your update_timestamp or modified timestamp will change based on every addition, subtraction or edit you have in this database row. Here is how it can be setup in PostgresSQL for example.
<changeSet id="{UNIQUE_ID}" author="{YOUR_NAME}">
<preConditions onFail="MARK_RAN">
<dbms type="postgresql"/>
</preConditions>
<createProcedure>
CREATE OR REPLACE FUNCTION refresh_updated_date_column()
RETURNS TRIGGER AS $$
BEGIN
NEW.updated_date = now();
RETURN NEW;
END;
$$ language 'plpgsql';
</createProcedure>
<rollback>
DROP FUNCTION IF EXISTS refresh_updated_date_column;
</rollback>
</changeSet>`
This will be an additional changeset that you will add after your original changeset of creating the table and adding the required columns.

Answer 3

You need to add CURRENT_TIMESTAMP in your csv file like:
"id","date_created"
"11236,CURRENT_TIMESTAMP
And your changeset like:
<column header="date_modified"
name="date_modified"
type="DATE"/>
Note: Im using liquibase version 4.2.0+