Revision as of 15:31, 12 September 2016

The following database rules explain the usage of the database called oedb, which will become a part of the openmod internet presence. For further details see also here.

Data Documentation

All data included in the databases has be documented! On this wiki page you learn, how to do so.
All abreviations have to be documentated in the

Naming of Data

The data in the database is organised in schemata and tables, which names are important to find around.

Database Name

The name of the database is oedb.

Database Schema

The structure of the database is realised via the naming of the schemata, which follows the following rules:

always lower case
no points, no commas
no spaces
no dates
use underscores

The name starts with the type of the schema:
1. orig for original data: Data that is directly available in other sources and underwent no editing other than transfering it to a data base friendly format
2. calc for processed data: Data that origin from original data or processed data via some script or other modifications. The specific data and methods used for this computations must be mentioned.
3. res for result data: Data that is the result of an energy model

The name includes the distinct subject area or source.

Example: orig_vg250

Database Table

always lower case
no points, no commas
no spaces
no dates
use underscores

The table name consists of

name starts with the source (e.g. zensus)
main value (e.g. population)
if separated by [attribute] (e.g. by_gender)
with resolution [tupel] (e.g. per_mun)

Example: zensus_population_by_gender_per_mun

Data Integrity

"Data integrity refers to maintaining and assuring the accuracy and consistency of data over its entire life-cycle." (Wikipedia) These two aspects belong to the data quality criteria, the data in the oedb should meet.

~~Data Integrity is one aspect of ensuring data quality the in the oedb.~~

General

Each table should have a single auto-incremented integer column as Primary Key with the corresponding table constraint.
Grant all privilegs to oeuser (automatically done by the system)

Geografic Data

Attribut name is geom.
Data type is geometry (or raster).
One of the Geometric Types is defined (https://www.postgresql.org/docs/current/static/datatype-geometric.html)
The CRS is defined as EPSG (http://spatialreference.org/ref/epsg/)
- Original data stays with the original CRS!
- Prefered CRS of the oedb are:

WGS84 - EPSG: 4326 (http://spatialreference.org/ref/epsg/4326/)
ETRS89 / ETRS-LAEA - EPSG: 3035 (http://spatialreference.org/ref/epsg/3035/)

Spacial index GIST

Data Referencing

There are several useful attributes on a table users have to know in order to work with the contained data efficiently. Therefore, ensuring the quality of these meta data is as important as ensuring the quality of the data itself (see also here).

For these meta data the documentation open-standard Json is used (Wiki and Json.org). The documentation is separated in two major categories:

Comments on schema: Contains metadata that define several aspects for the database schema
Comments on tables: Contains metadata that define several aspects for the whole table
Comments on rows: Store important informations on a specific row and the stored data

Comments on Schema

Schemata are used in the database in order to structure tables, functions, assign assignment of permissions and much more. For the documentation purpose a string in json format is set as comment on schema. The attribute names begins with an upper case and are given by the following definition for schemata.

Metadata Documentation of schemata
Attribute (level 1)	Attribute (level 2)	Description
Name		Original name of the data set
Description		Short description of the data set.
Changes		Information of changes and user
	Name	Name of Person created or changed dataset
	Mail	E-mail Address
	Date	Date of changes
	Comment	Comment of changes
Note		Field for notes or ToDo which are not done yet

SQL Json Example

Comments on Tables

Comments on a table are json-dictionary as strings that describe the overall structure of the corresponding table. For every field the corresponding unit (in case of numerical values) and a description that specifies the contained data should be attached. The attribute names begins with an upper case and are given by the following definition of Database Tables. The Json meta documentation string is stored as table comment on the database table.

Original Data (orig)

Original Data (orig) are defined as data from one source which are not further processed (see: Database Schema). The metadata Documentation for those data sets are set as a comment on the table. Following meta data are proposed:

Metadata Documentation of original data on table
Attribute (level 1)	Attribute (level 2)	Description
Name		Original name of the data set
Source
	Name	Source Name
	URL	URL string
Reference date		Reference date of the data set.
Date of collection		Date of data collection into the database.
Original file		Name of the original data file with file extension (e.g. .xls,.shp, .pdf, etc.)
Spatial resolution		Spatial resolution of the data set
Description		Short description of the data set.
Column		Metadata of all table fields / columns
	Name	Name of Column 1
	Description	English description of Column 1
	Unit	Unit if exist e.g. (€, MWh, etc.)
	…	...
	Name	Name of Column N
	Description	English description of Column N
	Unit	Unit if exist e.g. (€, MWh, etc.)
Changes		Information of changes and user
	Name	Name of Person created or changed dataset
	Mail	E-mail Address
	Date	Date of changes
	Comment	Comment of changes
ToDo		Comment of ToDo which are not done yet
Licence		Licence of the data set
	Name	Name of Licence
	URL	URL of Licence
Instructions for proper use		Instructions for proper use of Licences.

Json Example:

{
"Name": "Original name of the data set",
"Source":[{
 "Name": "Website of data",
 "URL": "www.website.com" }],
"Reference date": ["2013"],
"Date of collection": ["01.08.2013"],
"Original file": ["346-22-5.xls"],
"Spatial resolution": ["Germany"],
"Description": ["Example Data (annual totals)", "Regional level: national"],

"Column": [
 {"Name":"id",
 "Description":"Unique identifier",
 "Unit":"" },

 {"Name":"year",
 "Description":"Reference Year",
 "Unit":"" },

 {"Name":"example_value",
 "Description": "Some important value",
 "Unit":"EUR" }],

"Changes":[
 {"Name":"Joe Nobody",
 "Mail":"joe.nobody@gmail.com (fake)",
 "Date":"16.06.2014",
 "Comment":"Created table" },

 {"Name":"Joana Anybody",
 "Mail":"joana.anybody@gmail.com (fake)",
 "Date":"17.07.2014",
 "Comment":"Translated field names"}],

"ToDo": ["Some datasets are odd -> Check numbers against another data"],
"Licence": [{"Name":"Licence – Version 2.0 (dl-de/by-2-0",
 "URL": "http://www.govdata.de/dl-de/by-2-0]"],
"Instructions for proper use": ["Always state licence"],
"Label": ["Germany", "Example Data"]
}

Meta Documentation of original data collections from several sources:

In addition to the meta documentation described above, data tables (blue table in figure) which include data from several sources get a ref_id column. The ref_id links each row with a json documentation string (ref_data_json) in the database table public.reference_to_entries (green table in figure).This table also includes the ref_data_json column which links to all sources of the row to be referenced (blue). The ref_data_json string includes one jabref_entries_id for each source used. The jabref_entries_id is matched by one entries_id belonging to a source stored in the public.entries table (orange table).

Example: ER-Model

ERM references example

reference_to_entries table structure:

ref_id	ref_data_json	schema_name	tbl_name	changed_by	lastmodified
Reference ID	Json Documentation string	Name of the schema which includes the table “tbl_name”	Name of table with the data to be referenced	Name of user changing or creating this reference entry. (Automaticdefault setting)	Date of entry modification. (Automatic default setting)

Each row in the reference_to_entries table (green) contains a ref_data_json documentation string which links to the meta data in the Jabref table public.entries (orange).

Json documentation string structure on row:

Metadata Documentation of original data on rows
Attribute (level 1)	Attribute (level 2)	Attribute (level 3)	Description
Name			Name of the table to be referenced
Discription			Short description of the table
Column			Columns which need to be referenced
	<column name 1>		Column name 1, (original column name and spelling)
		jabref_entries_id	Jabref entries id of Literature entry
		Description	Short description
	<columnname2>		Column name 2, (original column name and spelling)
		jabref_entries_id	Jabref entries id of Literature entry
		Description	Short description
Note			Note or comment to this entry

Example:

Database table: ref_test.parameter_electrical_power_plant

fuel	type_of_generation	effnetto_el	...	opex_var	ref_id
coal	st	0.35	...	2	1
...

Database table: reference_to_entries table structure:

ref_id	ref_data_json	schema_name	tbl_name	changed_by	lastmodified
1	{ "Name": "Collection of electrical power plant parameter", "Discription": "Technical parameter of confentional electrical power plants …	ref_test	parameter_electrical_power_plant	user_1	2016-03-17 15:37:24.538213

Jsonref_data_jsonExample:

{
"Name": ["Collection of electrical power plant parameter"],
"Description":["Technical parameter of conventional electrical power plants "],
"Column": [{
 "effnetto_el":{"jabref_entries_id": 1,
 "Description":"Electrical net efficiency},
 
 "opex_var": {"jabref_entries_id": 2,
 "Description":"Variable operational expenditure"} }],

"Note":["Short note or comment to this entry"]
 }

Note: The general meta information like units are given meta documentation of the table.

The metadata BibTeX standard from JabRef is used for the Data Referencing in the table public.entries.

Processed and Result Data (calc/res)

The documentation rules for processed / calculated and results tables are equal the the original data.

As processed data does not necessarily have a simple source the fields "Source", "Original File", "Reference date" are commited. These information should be mentioned row-wise as explained in the next paragraph.

{"Name": "Results",
"Date of collection": ["01.08.2013"],
"Spatial resolution": ["Germany"],
"Description": ["Financial key figures of German municipalities (annual totals)", 
 "Regional level: municipalities, association of municipalities"],


"Column": [
 {"Name":"id",
 "Description":"Unique identifier,
 "Unit":"" },

 {"Name":"year",
 "Description":"Reference Year",
 "Unit":"" },

 {"Name":"example_value",
 "Description":"Some important value",
 "Unit":"EUR" }],

"Changes":[

 { "Name":"Autor1",
 "Mail":"Autor1@e-mail.com",
 "Date":"16.06.2014",
 "Comment":"Created table" },

 { "Name":"Autor2",
 "Mail":"Autor2@e-mail.com",
 "Date":"17.07.2014",
 "Comment":"Translated field names"}],

"ToDo": ["Some datasets are odd -> Check numbers against another data"],
"Licence": ["Datenlizenz Deutschland – Namensnennung – Version 2.0 (dl-de/by-2-0;
 [http://www.govdata.de/dl-de/by-2-0 http://www.govdata.de/dl-de/by-2-0])"],
"Instructions for proper use": ["Always state licence"]
"Label": ["Study", "Example Data"]
}

Comments on Rows

The comments on a row aim to enhance the reproducabilty of data that is present in the database by stating the underlying data that was used to compute this row as well as the applied computational methods.

During these processes some kinds of uncertainities might occur as well as the decissions (assumtions) that were made to deal with them. Examplatory, some values might be missing amid this row and a linear development during this period was assumed to fix this gap. Each row has to be annotated by a json dictionary that must contain the following fields:

origin: Link or textual description of the data set this row origins from.
method: Method used to calculate this row from above origin (e.g. Link to a python script)
assumption: A list of dictionaries. Each dictionary describes an assumption and annotates the affected rows.
- begin: First column affected by the assumption
- end: Last column affected by the assumption
- type: Type of the problem that had to be solved. Each type requires one or more additional keys in this dictionary. Possible types and their required additional keys are:
  - gap: A not all fields could be calculated and/or filled
    - solution: Method that was used to generate date to fill this gap (e.g. linear interpolation)

multiplicity: A field could be filled by several values
solution: Method that was used to select one value (e.g. Minimum)
values: Possible Values that could have been used

An examplatory dictionary:

{
"origin":"https://data.openmod-initiative.org/data/oedb/orig_db/table
"method":"https://github.com/openego/data_processing/blob/master/calc_ego_substation/Voronoi_ehv.sql"
"assumptions":
 [
 {
 "type": "gap"
 "begin": "step_15"
 "end": "step_34"
 "solution": "linear_interpolation"
 } 
 ]
}

@@ Line 182: / Line 182: @@
 <br/>
 ==== Original Data (orig)<br/> ====
@@ Line 192: / Line 193: @@
 |+ Metadata Documentation of original data on table<br/>
 |- valign="top"
-! style="border-width: 1px medium 1px 1px;  border-style: solid none solid solid;  border-color: rgb(0, 0, 0) -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0.1cm 0cm 0.1cm 0.1cm;  width: 198px;  height: 15px" scope="col" | <div>Attribute (level 1)<br/></div>
+! scope="col" style="border-width: 1px medium 1px 1px;  border-style: solid none solid solid;  border-color: rgb(0, 0, 0) -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0.1cm 0cm 0.1cm 0.1cm;  width: 198px;  height: 15px" | <div>Attribute (level 1)<br/></div>
-! style="border-width: 1px medium 1px 1px;  border-style: solid none solid solid;  border-color: rgb(0, 0, 0) -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0.1cm 0cm 0.1cm 0.1cm;  width: 131px" scope="col" | <div>Attribute (level 2)<br/></div>
+! scope="col" style="border-width: 1px medium 1px 1px;  border-style: solid none solid solid;  border-color: rgb(0, 0, 0) -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0.1cm 0cm 0.1cm 0.1cm;  width: 131px" | <div>Attribute (level 2)<br/></div>
-! style="width: 291px;  border: 1px solid rgb(0, 0, 0);  padding: 0.1cm" scope="col" | <div>Description<br/></div>
+! scope="col" style="width: 291px;  border: 1px solid rgb(0, 0, 0);  padding: 0.1cm" | <div>Description<br/></div>
 |- valign="top"
 | style="height: 15px;  width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" | <div>Name<br/></div>
@@ Line 204: / Line 205: @@
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div><br/></div>
 |- valign="top"
-| style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" rowspan="2" | <div><br/></div>
+| rowspan="2" style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" | <div><br/></div>
 | style="border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 131px" | <div>Name&nbsp;<br/></div>
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Source Name<br/></div>
@@ Line 235: / Line 236: @@
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Metadata of all table fields / columns<br/></div>
 |- valign="top"
-| style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" rowspan="3" | <div><br/></div>
+| rowspan="3" style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" | <div><br/></div>
 | style="border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 131px" | <div>Name</div>
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Name of Column 1<br/></div>
@@ Line 249: / Line 250: @@
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>...</div>
 |- valign="top"
-| style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" rowspan="3" | <div><br/></div>
+| rowspan="3" style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" | <div><br/></div>
 | style="border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 131px" | <div>Name</div>
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Name of Column N</div>
@@ Line 263: / Line 264: @@
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Information of changes and user</div>
 |- valign="top"
-| style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" rowspan="4" | <div><br/></div>
+| rowspan="4" style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" | <div><br/></div>
 | style="border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 131px" | <div>Name</div>
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Name of Person created or changed dataset</div>
@@ Line 295: / Line 296: @@
 | style="border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 131px" | <div><br/></div>
 | style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | <div>Instructions for proper use of Licences.</div>
-|-
-| style="width: 168px;  border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 198px" | Label
-| style="border-width: medium medium 1px 1px;  border-style: none none solid solid;  border-color: -moz-use-text-color -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0cm 0.1cm 0.1cm;  width: 131px" |
-| style="width: 291px;  border-width: medium 1px 1px;  border-style: none solid solid;  border-color: -moz-use-text-color rgb(0, 0, 0) rgb(0, 0, 0);  padding: 0cm 0.1cm 0.1cm" | Associated key words of data table
 |}
@@ Line 358: / Line 355: @@
 <br/>
 === Meta Documentation of original data collections from several sources: ===

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Revision as of 15:31, 12 September 2016

Contents

Data Documentation

Naming of Data

Database Name

Database Schema

Database Table

Data Integrity

General

Geografic Data

Data Referencing

Comments on Schema

Comments on Tables

Original Data (orig)

Meta Documentation of original data collections from several sources:

Processed and Result Data (calc/res)

Comments on Rows

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About

Help

Search

Navigation

Search

Interaction

Toolbox

Namespaces

Variants

Views

Actions

DatabaseRules

Revision as of 15:31, 12 September 2016

Contents

Data Documentation

Naming of Data

Database Name

Database Schema

Database Table

Data Integrity

General

Geografic Data

Data Referencing

Comments on Schema

Comments on Tables

Original Data (orig)

Meta Documentation of original data collections from several sources:

Processed and Result Data (calc/res)

Comments on Rows