Editing Attributes in ArcGIS Attributes – the data in records. e.g A parcel of land might be zone 3A residential. The field = TAG The attribute = 3A In this topic you will learn -Turn on the editing function - Open the attribute table - Identify the record that needs changing - Identify the field that needs changing - Change the attribute - Save the changes

Common Concepts Editing mode or outside editing mode Generally you should be in edit mode when you want to make a change to attribute information in a dataset. When you are in edit mode you can use the ‘undo’ option – very handy for stuff ups! However, if you are fairly confident that you know what you are doing and are happy to work outside the edit environment, then you can make some changes without turning on ‘edit mode’. The software will warn you about this, and give you the option to back out. Save edits – this is important, you don’t want to lose a days work! Undo – this is useful, it can help to quickly reverse a mistake.

‘Editor Mode’ To Start Editing a dataset – you must be in edit mode Step 1 - Make sure the ‘Editor’ tool bar is visible Step 2 – Start Editing (you maybe asked to select a folder) Step 3 – Make sure the target dataset is correct Note: if you cannot see all the tools then make your ArcMap window larger or move the tools down to the next level

Adding and Changing Attribute Information Step 1 – Open the attribute table to edit Step 2 – Find the record you want to edit (note you may have already selected this record – it will be blue in the table) Step 3 - Click on the cell and type in the new value Step 4 – Save your changes Step 5 – Stop editing when you have finished your editing session

Updating Attributes using a field calculator Sometimes you may want to add the same value to more than one record. To do this you use the field calculator Step 1- Highlight the entire column Step 2- click the options button (if you cannot see it try increasing the size of your attribute table) and select the calculate option Step 3 – Click on the field you wish to update Step 4 – Click on the function (if required) Step 5 – type in the value you want (or formula) Don’t forget to save edits and stop editing when finished Step 6 – Click OK Step 7 – Check the attribute information to make sure the changes are correct! Note – if you use the same calculation all the time you can save it, and then load it again when you need it.

Editing mode or outside editing mode Generally you should be in edit mode when you want to make a change to attribute information in a dataset. When you are in edit mode you can use the ‘undo’ option – very handy for stuff ups! However, if you are fairly confident that you know what you are doing and are happy to work outside the edit environment, then you can make changes using the field calculator without turning on ‘edit model’. If you use the field calculator from the attribute table without being in edit mode you will get a warning (see below). This gives you the option to back out.

Don’t Forget Save edits – try to do it as you go Finish editing – turn your edit session off

ADDITIONAL INFORMATION: - Complex updates (using field calculator) -Limits on data that can be entered for quality control (using the concept of ‘domains’). -Attribute Dialog box -Updating from the toolbox