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I have Comcast cable internet and the cable modem has a built-in wifi router. The wifi used to work fine, but now it often can't connect with some but not all of the computers in the house. With the Dell laptop I'm using (Windows XP) the router shows up very strong when scanning for signal, but connection fails. After a few hours it will sometimes connect and then work great for several hours before failing the same way. With a Lenovo computer it works solidly but an Ipad apparently doesn't find the signal at all. The hardware diagnostic on the Dell says everything is working. Any idea what's going on? 98.207.66.10 (talk) 00:36, 29 April 2013 (UTC)
What is the maximum size for reinscriptibles CD.
I know there are 900Mb CD-R, but I can't find the same size for CD-RW.2A02:8422:1191:6E00:56E6:FCFF:FEDB:2BBA (talk) 10:26, 29 April 2013 (UTC)
I'm trying to find a website or similar service I can create a group on for a club I'm part of, somewhere people can talk and post information on upcoming events and things like that, a sort of social networking place. I'd want something quick and easy for people to sign up to, too. I've considered facebook, google+ and skype, but none of them are quite what we want
anyone know of anything like this?
213.104.128.16 (talk) 15:22, 29 April 2013 (UTC)
Hey, guys. It's bugging me not to know this, so here goes. Say you have a Nintendo DS with a DS game loaded. You can normally wirelessly connect to another DS (for example trading Pokemon in the 4th or 5th generation games), BUT... is it possible between a DS and a 3DS, or two 3DS' with original DS paks loaded? Prompt answer, please. --JadeGuardian (talk) 17:38, 29 April 2013 (UTC)
I'm currently reading "Database System Concepts" by Silberschatz-Korth-Sudarshan. I was going through the section describing the strong and weak entity sets in an ER model. Here's the section. An entity set may not have sufficient attributes to form a primary key. Such an entity set is termed a weak entity set. An entity set that has a primary key is termed a strong entity set. As an illustration, consider the entity set payment, which has the three attributes: payment-number, payment-date, and payment-amount. Payment numbers are typically sequential numbers, starting from 1, generated separately for each loan. Thus, although each payment entity is distinct, payments for different loans may share the same payment number. Thus, this entity set does not have a primary key; it is a weak entity set. For a weak entity set to be meaningful, it must be associated with another entity set, called the identifying or owner entity set. Every weak entity must be associated with an identifying entity; that is, the weak entity set is said to be existence dependent on the identifying entity set. The identifying entity set is said to own the weak entity set that it identifies. The relationship associating the weak entity set with the identifying entity set is called the identifying relationship. The identifying relationship is many to one from the weak entity set to the identifying entity set, and the participation of the weak entity set in the relationship is total. In our example, the identifying entity set for payment is loan, and a relationship loan-payment that associates payment entities with their corresponding loan entities is the identifying relationship. Although a weak entity set does not have a primary key, we nevertheless need a means of distinguishing among all those entities in the weak entity set that depend on one particular strong entity. The discriminator of a weak entity set is a set of attributes that allows this distinction to be made. For example, the discriminator of the weak entity set payment is the attribute payment-number, since, for each loan, a payment number uniquely identifies one single payment for that loan. The discriminator of a weak entity set is also called the partial key of the entity set.
First, it was mentioned that the attribute payment_number can be the same for different loans, so, the entity set is weak. Then again, it's said that the attribute has unique values for the same loan. So, it can act as a discriminator. Why in one case, different loans are taken, while in the other, the same loan? In simpler words, why are not, in both cases, either multiple loans taken, or a single loan taken? — Preceding unsigned comment added by 117.197.254.199 (talk) 18:16, 29 April 2013 (UTC)
LOAN_PAYMENTS ============= *Loan number *Payment number Payment date Payment amount
LOAN_DETAILS ============ *Loan number Loan amount Loan period Loan origination date Loan interest rate Loaner Loanee
RIPOFF_BANK_PAYMENTS ==================== *Payment number Payment date Payment amount
REPO_BANK_PAYMENTS ================== *Payment number Payment date Payment amount