From: Joanna M. <jom...@gm...> - 2006-09-25 23:23:28
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Hi, My organization is trying to make some of our data available through a WFS, and we think that using GeoServer with a custom DataStore a good way to go about doing this. However, we are not a GIS shop, and don't have much in the way of GIS knowledge. So I feel like I'm groping around in the dark a little. The good news is that our data is fairly simple - just geographic points (lat/lon) representing earthquake events and seismographic stations. No lines or polygons. The data resides in an Oracle database and we may have Oracle Spatial capability, so in the short term our best answer may be to create views that map our current data into spatial data, and use the Oracle DataStore. But we're not 100% sure we have that capability, and even if we do, we have some architectural considerations that would make accessing the data via some Java classes preferential - both so we can provide mapping services to other seismologic data centers and also so we can potentially do some pre-filtering of results. The PropertiesDataStore example in the Data Wrangling makes building a custom DataStore look relatively straightforward. Given our underlying database requirements, I imagine we would want to base off the JDBCDataStore. Yet when I look at the code in the OracleDataStore (and dependent classes) the implementation doesn't look at all straightforward, especially if we can't use Oracle's Spatial Data Option. Is what we want to do even feasible? Has anyone done something similar? Any suggestions or directions would be much appreciated. And yes, if we do successfully implement, we will make our code available for learning off of. Thanks, Joanna Joanna Muench Software Engineer IRIS Data Management Center www.iris.edu |
From: Jody G. <jga...@re...> - 2006-09-26 01:11:43
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Joanna Muench wrote: > Hi, > > My organization is trying to make some of our data available through a > WFS, and we think that using GeoServer with a custom DataStore a good > way to go about doing this. However, we are not a GIS shop, and don't > have much in the way of GIS knowledge. So I feel like I'm groping > around in the dark a little. The good news is that our data is fairly > simple - just geographic points (lat/lon) representing earthquake > events and seismographic stations. No lines or polygons. Sweet. > The data resides in an Oracle database and we may have Oracle Spatial > capability, so in the short term our best answer may be to create > views that map our current data into spatial data, and use the Oracle > DataStore. But we're not 100% sure we have that capability, and even > if we do, we have some architectural considerations that would make > accessing the data via some Java classes preferential - both so we can > provide mapping services to other seismologic data centers and also so > we can potentially do some pre-filtering of results. Well the bare minimum you need is the ability to have a iterator over your data, there is an implementation called AbstractDataStore, and if you can subclass that an provide a FeatureReader (ie a normal java iterator that happens to throw IOExceptions) then the rest is kind of done for you. Not done well, but at least GeoServer can see something. > The PropertiesDataStore example in the Data Wrangling makes building a > custom DataStore look relatively straightforward. Given our underlying > database requirements, I imagine we would want to base off the > JDBCDataStore. Eeek, JDBCDataStore is not really designed (more kind of involved). If your needs are simple please start with AbstractDataStore. > Yet when I look at the code in the OracleDataStore (and dependent > classes) the implementation doesn't look at all straightforward, > especially if we can't use Oracle's Spatial Data Option. Is what we > want to do even feasible? Has anyone done something similar? Any > suggestions or directions would be much appreciated. Setting up a view (if you are allowed) and showing that with OracleDataStore is the least amount of effort. Creating a single purpose datastore (based on AbstractDataStore is also a good option). Are you needing to support writing as well? > And yes, if we do successfully implement, we will make our code > available for learning off of. That would be great, I am the author of that creating a datastore tutorial, so if you spot inconsistencies (and you will) please let me know. Jody |
From: Paul R. <pr...@re...> - 2006-09-26 15:00:08
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Joanna, If your Oracle is medium recent (9+) you should have Oracle Locator as part of your system, which will be all you need for this requirement. You don't need to write a DataStore, unless you want to for the intellectual exercise. Just add a trigger to your existing table of earthquakes that, on insert/update/delete maintains a parallel table of the same location information as SDO_GEOMETRY. Then you can have a spatial index on the table with SDO_GEOMETRY, and publish it using GeoServer and the normal Oracle datastore. You could also use a VIEW, but I don't know if you could apply a spatial index to the view, and that is probably a wise thing to do (assuming you have more than a trivial quantity of data). Paul On 25-Sep-06, at 4:23 PM, Joanna Muench wrote: > My organization is trying to make some of our data available > through a WFS, and we think that using GeoServer with a custom > DataStore a good way to go about doing this. However, we are not a > GIS shop, and don't have much in the way of GIS knowledge. So I > feel like I'm groping around in the dark a little. The good news is > that our data is fairly simple - just geographic points (lat/lon) > representing earthquake events and seismographic stations. No lines > or polygons. > > The data resides in an Oracle database and we may have Oracle > Spatial capability, so in the short term our best answer may be to > create views that map our current data into spatial data, and use > the Oracle DataStore. But we're not 100% sure we have that > capability, and even if we do, we have some architectural > considerations that would make accessing the data via some Java > classes preferential - both so we can provide mapping services to > other seismologic data centers and also so we can potentially do > some pre-filtering of results. > > The PropertiesDataStore example in the Data Wrangling makes > building a custom DataStore look relatively straightforward. Given > our underlying database requirements, I imagine we would want to > base off the JDBCDataStore. Yet when I look at the code in the > OracleDataStore (and dependent classes) the implementation doesn't > look at all straightforward, especially if we can't use Oracle's > Spatial Data Option. Is what we want to do even feasible? Has > anyone done something similar? Any suggestions or directions would > be much appreciated. > > And yes, if we do successfully implement, we will make our code > available for learning off of. > > Thanks, Joanna > > Joanna Muench > Software Engineer > IRIS Data Management Center > www.iris.edu > ---------------------------------------------------------------------- > --- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to > share your > opinions on IT & business topics through brief surveys -- and earn > cash > http://www.techsay.com/default.php? > page=join.php&p=sourceforge&CID=DEVDEV________________________________ > _______________ > Geotools-gt2-users mailing list > Geo...@li... > https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users |