Full-stack dev quiz question #49

Full-stack dev quiz question #49

It is obvious that nobody has to remember all the details that are easy to find in the documentation. But on the other hand, it is good to know the basic stuff to not waste time checking it every time. Check forty ninth question of full-stack dev quiz to verify how much you remember about data modifications using Liquibase.

Which sentence best describes the difference between value and valueComputed attributes in update change used in Liquibase? For example:

<changeSet id="Update A" author="DBA presents">
  <update tableName="test_table">
    <column name="col1" value="abc" />
  </update>
</changeSet>

<changeSet id="Update B" author="DBA presents">
  <update tableName="test_table">
    <column name="col1" valueComputed="abc" />
  </update>
</changeSet>

Choose the best sentence.

1. valueComputed is optimized for performance before the changeset is actually applied, value is parsed when it is applied
2. value works for all data types but valueComputed only for numerics
3. valueComputed is dedicated to computed columns in the database, value is for persisted columns
4. Both do exactly the same, valueComputed is there for backward compatibility
5. value is for constant values, valueComputed can be used with expressions

For the correct answer scroll down

.

.

. 

.

.

.

The correct answer is: e. If you would like to read more, check Update data based on another column with Liquibase article.