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Jan
17
answered should I denormalize for user profiles?
Dec
23
answered Does an order by clause have a negative effect on performance?
Dec
12
revised why in explain in mysql row count is very high
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Dec
12
answered why in explain in mysql row count is very high
Nov
22
answered How to add foreign key with more than 1 field in SQL Power Architect
Nov
22
answered Does any SQL engine have navigation support in CHECK clauses?
Nov
6
answered Best data modeling approch to handle redundant foreign keys in relational model
Oct
2
comment Explaining 2NF vs 3NF with an example
@philipxy When we have multiple candidate keys, we choose one as primary for use in relationship This choice may change as more data becomes available. My use of non-prime should have been rather than non-primary, as at some point you need to pick one of multiple candidate key for use in relationships. Subject_name remains a candidate key in the subjects table and remains both prime and transitive in that table. A database implementation would likely include a unique key on subject_name.
Oct
2
revised Explaining 2NF vs 3NF with an example
Correct usage of prime vs primary.
Oct
2
revised Explaining 2NF vs 3NF with an example
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Sep
29
answered 1NF vs BCNF cons and pros
Sep
27
revised Explaining 2NF vs 3NF with an example
Improve answer.
Sep
24
answered Explaining 2NF vs 3NF with an example
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23
awarded  Nice Answer
Aug
1
revised Is a Junction Table the same as a Weak Entity?
Fix wording
Feb
26
answered Check attribute table referenced foreign key
Feb
14
awarded  Yearling
Jan
1
answered Should I group by and then join, or join and then group by?
Dec
1
answered How do I call a collection of tables with normalized (generic) information
Nov
29
comment If a database is in memory does it still need indexing?
If the query has an explicit or implicit limit, it may not need to scan the whole table. If a cursor is being used, it will stop scanning when it matches a row and resume scanning when the next row is requested.