Query not updated with new value using arcpy.da.UpdateCursor()? [closed]

Question

What is wrong with this code?

query='"depth">1700 AND "depth"<1750'

with arcpy.da.UpdateCursor(out_layer,"depth",query)as cursor:
    for row in cursor:
        row[0]=0
        cursor.updateRow(row)

My query is not updated with the new value.

Answer 1

I'd suggest using the AddFieldDelimiters function. This allows you to enter a field name and a data source, and the field delimiters are automatically added.

field = arcpy.AddFieldDelimiters(out_layer, "depth")
query = """{0} > 1700 AND {0} < 1750""".format(field)

with arcpy.da.UpdateCursor(out_layer, "depth", query) as cursor:
    for row in cursor:
        row[0] = 0
        cursor.updateRow(row)

This is assuming out_layer is a valid layer.

Answer 2

You don't need double quotes around the field names. If you depth field is numeric, use this:

query = '''depth > 1700 AND depth < 1750'''

Also, enclosing the query with triple quotes is a good way to make sure the quotes delimiting the query won't be matched with the quotes delimiting field values within the query.