Lookup fields referring to tbls w/o relationship
in [Tables]
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From: Jeff Boyce on 8 Jan 2010 11:52 Whether you explicitly draw the relationship to Access' attention or not, the relationship exists. I'm not sure I understand the issue you're describing/attributing to combobox use, but if you KNOW there's a relationship among tables, why not let Access in on it...? Regards Jeff Boyce Microsoft Access MVP -- Disclaimer: This author may have received products and services mentioned in this post. Mention and/or description of a product or service herein does not constitute endorsement thereof. Any code or pseudocode included in this post is offered "as is", with no guarantee as to suitability. You can thank the FTC of the USA for making this disclaimer possible/necessary. "Pamela" <Pamela(a)discussions.microsoft.com> wrote in message news:6FCB7ADE-726E-4E63-AD53-625BEAA231E5(a)microsoft.com... > Hi Jeff, > > I must not be phrasing my ultimate question well...so sorry. I recognize > that there COULD be...and yes, that would be a one-to-many - we deal w/ > multiple insurance companies all of which have multiple claims. But how > does > it work with combo boxes like that that I didn't need a relationship > between > Claim & InsuranceCompany and what are the benefits of setting up that > relationship? How will my data work differently with that relationship > established and am I making those relationships a bigger deal than what > they > are? They always seem a little scary to me so if I can skip along without > some of them, it's a little tempting but I don't want to hinder my db for > the > future. > > Thanks so much for clarifying this for me! > > Pamela > > "Jeff Boyce" wrote: > >> Pamela >> >> Are you saying that your database covers more than one insurance company? >> If so, it seems to me (*from the outside!*) that one insurance company >> could >> be related to many claims (Company A covering 1,000 claims, Company B >> covering 525 claims, etc.). >> >> If that describes your situation, the there IS a relationship between the >> InsuranceCompany and the Claim. >> >> Does that help? >> >> Regards >> >> Jeff Boyce >> Microsoft Access MVP >> >> -- >> Disclaimer: This author may have received products and services mentioned >> in this post. Mention and/or description of a product or service herein >> does not constitute endorsement thereof. >> >> Any code or pseudocode included in this post is offered "as is", with no >> guarantee as to suitability. >> >> You can thank the FTC of the USA for making this disclaimer >> possible/necessary. >> >> "Pamela" <Pamela(a)discussions.microsoft.com> wrote in message >> news:A6B99EB1-3FB7-489F-BC38-39C4938FF45D(a)microsoft.com... >> > Hi Jeff, >> > >> > In my research, I understand that it is always best to have items in a >> > table >> > relate to 1 topic only. In the case of our business, we inspect cars >> > that >> > have been in an accident for the insurance companies. In the case of >> > this >> > db, the only purpose it was originally to serve was to take info about >> > the >> > inspection and concatenate it into a paragraph complete with our legal >> > verbage, disclaimers etc., which we then have to paste into the >> > insurance >> > company's online system. >> > >> > With this in mind, I broke the tables down into these: tblClaim, >> > tblInspection (date of, etc) , tblLocation (where it took place), >> > tblDamage >> > (classifying the damage, the measurements of, etc) and tblEstimate. >> > For >> > this >> > purpose, I felt a one-to-one was best. Each claim has 1 inspection, 1 >> > location, 1 set of damage info, 1 estimate, etc all joined around our >> > central >> > assignment # which is the PK on all of the tbls and which I use for the >> > relationships. I have other tables that I use to populate my cbos and >> > those >> > are really from where my question stems. I have tblInsuranceCompany >> > which >> > populates cboInsuranceCompany but there is no direct relationship that >> > I >> > needed to make for it to work and work well, as I stated before. Is it >> > sufficient to leave it as it is or if I decide to expand upon my db >> > will I >> > run into issues because it doesn't have a direct relationship >> > established? >> > Thanks so much! >> > Pamela >> > >> > "Jeff Boyce" wrote: >> > >> >> Pamela >> >> >> >> Access is a relational database. It is optimized to work with >> >> well-normalized data. >> >> >> >> It is somewhat rare to have a number of tables related one-to-one in a >> >> well-normalized relational database. That usually only happens when >> >> you >> >> have "sub-typing". For example, you could have a list of equipment at >> >> your >> >> work, but of different types, each with different characteristics >> >> (e.g., >> >> Computers, Desks, Chairs, Bookcases, ...). You might decide to create >> >> one >> >> table to "inventory" them all, giving each a unique inventoryID, but >> >> use >> >> separate tables to hold the particulars on each different class/type >> >> of >> >> equipment (i.e., chairs don't have the same characteristics that >> >> computers >> >> do). That's a one-to-one situation. >> >> >> >> The only one who knows if the things about which you are collecting >> >> data >> >> are >> >> related is you. Access can't tell that. We can't help with that >> >> unless >> >> you >> >> describe your situation a bit more. >> >> >> >> More info, please... >> >> >> >> Regards >> >> >> >> Jeff Boyce >> >> Microsoft Access MVP >> >> >> >> -- >> >> Disclaimer: This author may have received products and services >> >> mentioned >> >> in this post. Mention and/or description of a product or service >> >> herein >> >> does not constitute endorsement thereof. >> >> >> >> Any code or pseudocode included in this post is offered "as is", with >> >> no >> >> guarantee as to suitability. >> >> >> >> You can thank the FTC of the USA for making this disclaimer >> >> possible/necessary. >> >> >> >> "Pamela" <Pamela(a)discussions.microsoft.com> wrote in message >> >> news:3920FBBF-CDD4-4067-AF48-57A6C377EF7D(a)microsoft.com... >> >> >I created a db and in reading now about db structure, I've seen a lot >> >> >of >> >> > mention of relationships. My db started out very simple with the >> >> > tables >> >> > that >> >> > I used for relationships all being one-to-one and now I'm >> >> > considering >> >> > adding >> >> > to it. In it, however, I also have some tables that I used (not w/ >> >> > the >> >> > Lookup Wizard but on my own) simply as lookup - populating cbos. I >> >> > didn't >> >> > seem to need to set relationships with these though for it to work >> >> > and >> >> > work >> >> > well. Why didn't it require a relationship and what are the pros & >> >> > cons >> >> > of >> >> > setting them up this way vs. w/ a relationship? >> >> > Thanks so much for your help! >> >> > Pamela >> >> >> >> >> >> . >> >> >> >> >> . >> |