Document: https://doc-stage.usersys.redhat.com/documentation/en/red-hat-jboss-enterprise-application-platform/7.0/single/development-guide#about_scalar_functions

13.4.9. About Scalar Functions talks about "standard" and "additional" functions.
13.4.10. HQL Standardized Functions talks about the "standard" ones. However, there is not section about the additional ones.

Suggestions for improvement:

• Explain what are the scalar functions or rename the section.
• Merge the two sections into one or make 13.4.10. HQL Standardized Functions a subsection of 13.4.9. About Scalar Functions
• Introduce the "additional" functions at the same level as the "standard" ones.
• Move 13.4.11. About the Concatenation Operation to 13.4.9. About Scalar Functions, too
• Show an example which uses one of the functions.

Some typos in these sections:

• Performs a SQL cast. - should be "an SQL"
• Performs a SQL extraction - should be "an SQL"
• addSqlFunction is not highlighted as code