===== conventions for metadatabase tables ====

=== Tables ===
niota tables that are part of the core system always start with "et_" or "etx_". The prefix "etx_" is used when it's some sort of extended table and for tables that may also be used by the customer for it's own configuration entries.

=== Views ===
Every view of the core system start with "v_" followed by the name of the "primary" table for this view.


=== Columns ===
Column names in metadatabase tables are built by an internal logic. The first part of the column name carries information about it's logical/business meaning, the second part of the column name tells something about it's specific usage.

The "business" meaning can for example be:
  * lastname of somebody
  * firstname of somebody
  * date of something
  * connection name for something
  * flag or indication of something
  * description of something
  * username of something
  * sortorder of something


The specific usage is then fixed be the second part.

Therefor a column that contains a connection name for logging is build by 

**conn_name** ... the overall info that the content will by a name of a connection\\
+\\
**logging** ... for what this connection name will be used (or log or logged).

The type of the column must be the same as for the "master domain" for connection name. The type can be found in the table et_**connection**.

result:
**conn_name_logging varchar(16)**

it's not logging_connection or logging_conn or something like this.

For a timestamp the column name usually has to start with **"ts_"** followed by the specific usage.\\
For a date the column name usually has to start with **"date_"** followed by the specific usage.\\

**ts_log** ... timestamp of log entry\\
**date_activation** .... date of activation\\

other examples

username .... main domain for username\\
username_owner ... username for data owner of a table\\

**icon** .... main domain for an icon filename\\
**icon_linked_table** column that contains an filename for an icon - used for the linked table in a master/detail link\\
**icon_linking_table** .... \\

it's not linked_table_icon or linkedicon