Time Format Alternate Half Year

From FMR Knowledge Base
Jump to navigation Jump to search

At ESCB level SDMX data exchanges, there is an agreement to use 'H' as the frequency value for semi-annual observations. This is specified via 'YYYY-H1' or 'YYYY-H2'.

The Registry supports this with a system property. When this is enabled the Registry is in 'alternate half year' mode. Under this mode:

  • Frequency value 'H' means half-year (semiannual or semester) as does frequency value 'S'. They are interchangeable as input.
  • 'YYYY-S1' and 'YYYY-H1' are valid TIME_PERIOD formats for half-yearly observations.
  • Output in SDMX-ML 2.1 will always be in the 'S' format (e.g. an input of 'YYYY-H1' will be converted to 'YYYY-S1'). This ensures that the output is correct to the SDMX specification.
  • Output in other formats will not be converted from 'H' to 'S' (e.g. SDMX-CSV)
  • The hourly frequency is not supported.

'Alternate half year' mode is controlled at system level on Registry start-up by setting the Java System variable "TF_ALTERNATE_HALF_YEAR" to "true".

Setting System Property

If using Apache Tomcat, it is recommended to set the value via JAVA_OPTS and using the setenv.bat or setenv.sh file:

(For Windows systems)
(For Unix systems)

Different procedures may be required for other web application servers like JBoss.

Is Alternate Half-Year Format set?

On startup the Fusion Registry system log will report the following message:

2021-12-31 23:59:59.123 INFO main io.sdmx.core.fmr.application.FusionRegistryApplicationInitialiser - Using 'Alternate Half-Year' Setting

Active system properties can also be queried using the REST API which is detailed here.