A Relational Query Optimizer ____

question 55

Multiple Choice

A relational query optimizer ____.

• A) is a form of a relational catalog
• B) is a separate piece of software that can be added to the relational DBMS environment as an option
• C) can be invoked at the option of the user issuing the query
• D) is only used with queries involving joins
• E) None of the above.

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Definitions:

DNA Profiling

A technique used to identify individuals by characteristics of their DNA, commonly used in forensic science to assist in identifying individuals or determining parentage.

DNA Regulatory Elements

Sequences of DNA that control the expression of genes, acting as switches to turn genes on or off.

Genomic Library

A collection of DNA fragments that represent the entire genome of an organism, which are stored in and can be propagated in a suitable host organism.

cDNA Library

A collection of complementary DNA (cDNA) clones that represent the mRNA transcripts present in a cell or tissue, used for gene expression studies.