In system applications, in order to obtain the point value set of element geometric fields, we used to think of arcengine for development and analysis. Here we will introduce a quicker method, the database st function provided by SDE can be directly parsed using SQL statements.
1) configure the Oracle External function library
To execute the st function in Oracle, you must first configure the following content.
A. Configure oracleextproc. For details, see the appendix "Configure Oracle EXTPROC to use SQL to access the geographical database ".
B. Update the Oracle database entry of st_shapelib. You can run the create or replace library SQL statement to complete the update.
For example, if st_shapelib.dll has been placed on a Windows server in a folder named libraryfiles, the statement should be:
Create or replace library st_shapelib
'C: \ libraryfiles \ st_shapelib.dll ';
On a Linux server with a directory named libfiles, the statement should be:
Create or replace library st_shapelib
'/Usr/libfiles/libst_shapelib.so ';
2) execute the SQL script
Is the attribute structure of a surface element class, where shape is a geometric field.
By performing a SELECT statement on the data, you can query the coordinate set of related geometric nodes. The details are as follows:
The returned clob type data can be used to obtain the decimal result, as follows:
Since Oracle configuration involves a lot of content and has been mentioned in the relevant help manual, I will not detail it in this blog. If you need relevant documents, you can leave an email to ask for them.