globally changing street to st. on records

@Donna Marino, seconding what @Joe Moretti and @Dariel Dixon both suggested.

If you want to do it cheaply, go with the Import route. I've done this myself cleaning up our database years ago with no complications. The issue of people's names is easily solved by either (1) only importing the street line itself) or (2) highlighting the Address1 column only when you do your Find-Replace. Also make sure to include a space before and after the word to make sure you don't grab compound names: for example, find-replace “ street ” instead of “street”. To be truly compliant with USPS codes, you would need to check all your abbreviations (route, blvd, avenue, suite, road, highway, apartment, etc) as well as your directions (NW, SW, etc), and remove any punctuation in the lines.

If your system is riddled with consistent errors, however, it implies that it has been several years possibly since your last complete Address Update service. This suggests you may have numerous out of date addresses in your file. Rather than a standard NCOA update, you may benefit from an AddressFinder or Enhanced NCOA update at this point, to hunt back 48 months for past moves. A professional data append will not only format your addresses, but ensure that they are current. The one downside, aside from price, is that you may wish to review select records before importing them, or be discriminating in your select query, to avoid inaccurate updates for priests, clerics, college students, and other high-risk move groups.

A middle ground (especially if your mail file is not too large) is to create a free account with the USPS IMSB small business tool. This tool allows you to create your own bulk mail files directly with the post office, and part of the process is that it passes your mail list through the USPS's NCOA service and gives you an output file. As I said, it's free, and you'll get updated addresses back 12 months, already formatted with Blvd, St, Ave, etc. You can process 10K records in one sweep, or split a larger file into multiple sweeps. The one drawback is that it spits it out all in capital letters, so if you don't like capital case, you will need to still convert to proper case, and then Find-Replace certain digits (like Nw to NW, 1St to 1st, etc) before importing into RE.