The Mycenaean Atlas Project is a database which accurately maps more than 1600 Mycenaean find spots. Because there are lat/lon pairs for every geographical
point the data in this database can be displayed with map products such as
Google Earth or GIS products like Carto and others.
Querying the MAP database: Select pk, pn, lat,lon from site where region = 'Laconia'; |
This MAP database is a relational database. The data is stored in several different
tables which are linked or connected through a primary key. Since the fundamental data concept in this
database is Mycenaean find spots it makes sense that each Mycenaean find spot
has its own unchanging primary key value.
Any table in the database that has information about a Mycenaean find
spot is accessed through the find spot primary key.
FIELDS in the 'Site' TABLE
The fundamental table in this database is the ‘site’
table. There is one unique record in the
‘site’ table for each find spot. The
record contains the following fields:
pk: the unique primary key designating this site
pn: (‘place name’) An alpha-numeric string with a
pronounceable name for the site, e.g., ‘Mycenae’, ‘Tiryns’, ‘Nestor’s Palace’, ‘Pallantion’.
Lat: the latitude field is a floating-point number with at
least six digits in the fractional part.
In the DB it is defined as ‘DOUBLE’.
Lon: the longitude field is a floating-point number with at
least six digits in the fractional part.
In the DB it is defined as ‘DOUBLE’.
Acc: ‘Accuracy’. This
is a value that expresses the degree of confidence in the lat/lon pair. See this for a full explanation.
Alt: Altitude in meters.
These altitudes in meters were derived from Google Earth.
Type: A single word identifier that gives a general
characterization for the site. The most
common types are: ‘Hab’, ‘Cem’, and ‘Ceramics’.
Comment: A character
field that can be used for information that clarifies the site record. Ordinarily this field is null.
Region: This is a character field of up to 45
characters. It is used to designate the
general geographic area in which the site is located. It holds such values as ‘Laconia’, ‘Attica’, ‘Argolid’,
‘Messenia’, etc.
SAMPLE QUERIES
These nine fields are all that is required to generally
characterize a find-spot. With just this
table it is already possible to write queries such as:
1.select * from site; // returns all info in the table
2. select pk, pn, lat, lon from site; // returns a file or all sites and
which is suitable for importing into Google Earth
3. select pk, pn, lat, lon from site where region =
‘Laconia’; // returns a file,
suitable for importing into Google Earth which shows all Mycenaean sites in
Laconia.
4. select pk, pn, lat, lon from site where alt < 50; // returns a file showing Mycenaean
sites close to a sea shore.
Habitations close to the shore. Query is: select pk, pn, lat, lon from site where alt < 50; |
5. select avg(alt) from site where type = ‘Hab’; // returns the average altitude of a
Mycenaean habitation.
Is the average burial above or below the average habitation? Use query 6
along with query 5:
6. select avg(alt) from site where type = ‘Cem’;
The following illustration shows those sites which range from 20 m. below to 20 m. above the average altitude of 191 m.
Mycenaean sites at about the average elevation of 191.4 m: Query: select pk, pn, lat, lon from site where alt > 171.4 and alt < 211.4; |
7. select count(*), region from site group by region; // This query will return a table with the
number of Mycenaean find spots in each region.
When you execute this query the first few rows will look like this:
318, Messenia
189, Argolid
137, Boeotia
105, Dodecanese
94, Achaea
81, Laconia
61, Attica
60, Ionian Islands
The other tables in the database support the 'site' table. By adding those tables we can write much more sophisticated queries. I will describe those tables and their potential interactions in follow-on posts.
Anyone who would like to have a copy of the MAP database can send an e-mail to bobconsoli 'at' gmail.com or leave a comment to any of my posts. To run the MAP database requires a SQL server running on your desktop computer. MySQL is such a server and it is powerful, industry-standard, and free.
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