database 
The 
database module provides functions for interacting with the database
 Functions 
| Function | Parameters | Return Value | Description | 
| db_select (query) | query: String containing a valid HQL select query 
 | A list of rows containing lists of column values | Note that only the HQL language is supported! 
 Data will always be returned in the same format:
 
 multiple_rows = [[column_a, column_b], [column_a, column_b]] single_row = [[column_a, column_b]]
 | 
| db_modify (query) | query: String containing a valid HQL modify query 
 | Amount of rows modified | Note that only the HQL language is supported! | 
| sanitize_value (value) | value: Object you want to put in a HQL query 
 | Your object sanitized and embedded in quotation marks | Sanitize a input for usage in a HQL query. This should always be used when formatting data into a query! The following objects are put into the correct format for a HQL query: uuid.UUID,java.util.UUID,java.util.Date | 
| convert_python_id_for_hql_query (python_id) | python_id: String containing a python id 
 | Valid HQL attribute name | Several words are reserved in Java and overlap with python ids that were used in customizing. To refer to them in a HQL query or when interacting with a pojo object you must specify the correct attribute name. This function returns the valid attribute name for a given python id. | 
Reserved words changed by 
convert_python_id_for_hql_query:
 Examples 
 Selecting all objects where a date attribute is unset 
from customizing import utilities
# Select all resource assignments that don't have an actual end set
query = """SELECT ras.id 
           FROM ResourceAssignment ras
           WHERE ras.actual_end != '01.01.1970'"""
utilities.db_select(query)
 Using sanitize value to use a java.util.Date object in a query 
from customizing import utilities
# Data event that is run when attendance is modified
def write_attendance_to_period(event, entity):
    # Read data from pojo
    resource = entity.resource  # String
    date = entity.date  # java.util.Date
    query = """select
                 a.duration,
                 a.type
               from
                 Attendance a
               where
                 a.resource = {resource}
               and
                 a.date = {date}""".format(resource=utilities.sanitize_value(resource), 
                                           date=utilities.sanitize_value(date))
    result = utilities.db_select(query)
    # ...
 Reading a pojo attribute safely with convert_python_id_for_hql_query 
from customizing import utilities
def read_pojo_attribute(pojo, python_id):
    attribute_name = utilities.convert_python_id_for_hql_query(python_id)
    return getattr(pojo, attribute_name)
pojo = utilities.create_entity('Project')
# Querying pojo.uuid raises an exception, the correct attribute is pojo.id!
uuid = read_pojo_attribute(pojo, python_id='uuid')