SQL Anywhere supports the Environmental System Research Institute, Inc. (ESRI) shapefile format. ESRI shapefiles are used to store geometry data and attribute information for the spatial features in a data set.
An ESRI shapefile includes at least three different files: .shp, .shx, and .dbf. The suffix for the main file is .shp, the suffix for the index file is .shx, and the suffix for the attribute columns is .dbf. All files share the same base name and are frequently combined in a single compressed file. SQL Anywhere can read all ESRI shapefiles with all shape types except MultiPatch. This includes shape types that include Z and M data.
The data in an ESRI shapefile usually contains multiple rows and columns. For example, the spatial tutorial loads a shapefile that contains zip code regions for Massachusetts. The shapefile contains one row for each zip code region, including the polygon information for the region. It also contains additional attributes (columns) for each zip code region, including the zip code name (for example, the string '02633') and other attributes.
The simplest ways to load a shapefile into a table are with the Interactive SQL Import Wizard, or the st_geometry_load_shapefile system procedure. Both of these tools create a table with appropriate columns and load the data from the shapefile.
You can also load shapefiles using the LOAD TABLE and INPUT statements, but you must already have created the table with the appropriate columns before performing the load operation.
To find the columns needed when loading data using the LOAD TABLE or INPUT statements, you can use the sa_describe_shapefile system procedure.
For a working example of loading a shapefile into a SQL Anywhere database, see Tutorial: Experimenting with the spatial features.
For more information about querying within a shapefile, see Openstring expressions in a FROM clause.
For more information about ESRI shapefiles, see http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf.
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