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| Expert | Average Ratings | Expertise |
|---|---|---|
Iain M WatsonU.S.
Available
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I have 15 years of SQL experience in several large scale business catagories. I have many programs involving complicated SQL queires in both DB2 and Orcale databases. I have many years experience dealing with Database administrators in performance/tuning and implementing large scale SQL systems. | |
Carlson LimU.S.
Available
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I can answer questions about database design for OLTP and OLAP. I can can answer questions about logical models and physical star schema models. I can answer questions on ERwin. | |
Suchitra JoshiU.S.
Available
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I can answer questions related to database (mainly Oracle), database architecture, design and programming. I can also answer questions related to SQL, Import/Export, SQL Loader etc. |
Hi, this look like a relational databases question ?? If so then we are talking about existence dependency. Existence dependency describes whether an entity in a relationship is optional or mandatory.
Hi, I am not sure which database you are using, but most SQL is the same in relational databases. You need to use the count and group by verbs to the existing joins you are doing:- Select count(*)

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