topic How can I select every other record in a very large attribute table other than interactively? in State & Local Government Questions

How can I select every other record in a very large attribute table other than interactively?

CherieMoritz2 — Fri, 03 Nov 2017 15:42:46 GMT

I am using ArcMap 10.5.1. My table contains pairs of parcel numbers and looks like this. Thank you.

Re: How can I select every other record in a very large attribute table other than interactively?

XanderBakker — Fri, 03 Nov 2017 15:55:18 GMT

It seems like the table is sorted on PARCEL_NO. Would it be possible to sort this table and create a new table, or is that not an option. This would probably create new OBJECTID and that would allow you to select by attributes using the following SQL:

MOD (OBJECTID, 2) = 0‍

Re: How can I select every other record in a very large attribute table other than interactively?

JoshuaBixby — Fri, 03 Nov 2017 16:07:26 GMT

Given a parcel number, which address to you want to select? The low or high address, e.g., 1066 Pine St or 1068 Pine St?

Re: How can I select every other record in a very large attribute table other than interactively?

CherieMoritz2 — Fri, 03 Nov 2017 20:22:42 GMT

The table order is important in this case. Cherie

Re: How can I select every other record in a very large attribute table other than interactively?

CherieMoritz2 — Fri, 03 Nov 2017 20:23:35 GMT

Either all the high addresses or all low addresses. It doesn't matter which, as long as it's consistently high or low. Cherie

Re: How can I select every other record in a very large attribute table other than interactively?

JoshuaBixby — Sat, 11 Dec 2021 22:56:20 GMT

You can generate an OID list and then pass every other element to Layer.setSelectionSet:

lyr = # ArcPy mapping layer object
fields = ["OID@", "PARCEL_NO", "WHOLEADDRESS"]
sql = "ORDER BY PARCEL_NO, WHOLEADDRESS"

with arcpy.da.SearchCursor(lyr, fields, sql_clause=(None,sql)) as cur:
    oid_list = [row[0] for row in cur]

lyr.setSelectionSet("NEW", oid_list[::2])


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Re: How can I select every other record in a very large attribute table other than interactively?

CherieMoritz2 — Mon, 06 Nov 2017 13:26:20 GMT

That's great! Thanks for your help. I will give it a try. Cherie