Again, still assuming the fields are the same. Once we have theįields, we pass into the cursors. ListFields isįaster, while Describe provides multiple properties, such as data type, fields, indexes, and many others. We can grab the attributes with arcpy.Describe or the arcpy.ListFields function.
#Arcobjects icursor full
The overall goal is to replace the SHAPE token reference with the full geometry token. We can deal with this SHAPE issue in many ways. Or multipoint features can only be created using the token which will cost us some performance and extra lines of code. When using * (field list), geometry values will be returned in a tuple of the x,y-coordinates (equivalent to the ~EsriĪgain, this default is fine if inserting points with an InsertCursors (and non-existent for tables). Yes, even faster than the Append Tool itself.
This means if we want to load point data, the performance will be much better than for Accessing geometry can be an expensive operation, so the default Geometry token is Why does this happen? Performance defaults. It will finish running with other attributes populated, but previewing the map will This is technically documented, but it can be confusing why our previous sample would work on tables and point layers, then suddenlyįail (silently) on a line or polygon layer. There is a small issue with the default SHAPE field when updating multi-point, line, or polygon data. If we are loading point data or table data, this will work without issue if the fields list and field order match. SearchCursor ( "C:/input.gdb/newPoints", "*" ) as cursor : for row in cursor : #Insert into the target dataset (only Points or tabular data if using an asterisk) InsertCursor ( "C:/out.gdb/Points", "*" ) # Setup a search cursor on our new data and interate the rows with arcpy. # Create an InsertCursor on our Target dataset
#Arcobjects icursor code
We will set up our new InsertCursor at the beginning, and with one more line of code inside the SearchCursor loop, we can add How would we load into our target layer? Let’s add the InsertCursor to our working Let’s assume our schemas are identical for now. If not, you will need to define the fields. If you know your input and target layers have the same schema and field order youĬan use the wildcard approach. When working with SearchCursorsĪnd InsertCursors, we don’t have the same luxury. Matching fields or if the field names/types are the same, allow the tool to take care of it for you. The great thing about the Append Tool is the ability to auto-match fields with the schema_type parameter.
#Arcobjects icursor how to
If the attributes are specified, the SearchCursor will maintain the attribute order as listed so we know how to access them. The issue with the wildcard attribute approach (asterisk) is knowing how to access the correct attribute of interest. Once we have access to every row of input data, we can insert the records into another layer, or even manipulate the attributesīefore loading. SearchCursor ( "C:/input.gdb/newPoints", "*" ) as cursor : for row in cursor : #Do stuff with each row # Setup a search cursor on our new data and iterate the rows with arcpy. There are some limitations with the asterisk which we will get into later. To access all fields from the input table. Use an asterisk (*) instead of a list of fields if you want This SearchCursor requires a minimum of two parameters, the input features (FeatureĬlass, Layer, Table, Table View), and a list of field names. These features we can use a SearchCursor. SearchCursorįirst, we need to read the input features from a Feature Class that we want to append somewhere.
No need to discuss the old ones, just disregard them and just use the new arcpy.da. If using ArcMap, there are two different classes ofĬursors - old and new. In our case, we are going to read and write features. Cursors can include a SQL clause or deconstruct features into their individual pointsĪ cursor is a data access object that can be used either to iterate through the set of rows in a table or to insert new rows A Cursory OverviewĬursors are an extremely fast way to read/write features while giving you lots of control over the features, attributes, andįilters. SearchCursor on source input data, and an InsertCursor on a Target schema to show how we can replicate or enhance our Python script.īoth the Append Tool and the Cursor approach have their pros and cons - just nice to have some options. Instead of calling theĪppend Tool, we can use cursors to append data and open the door to other data manipulation options. It also doesn’t give us access to the data before loading.
However, calling a Geoprocessing toolįrom Python doesn’t feel very Pythonic. If we are using Python with ArcGIS, there are existing tools to append data.
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