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EVALUATION EXAM Q&A: 2026 STUDY GUIDE
100% CORRECT
◍ HTML. Answer: Formatting tags in <>
◍ Ident & Auth. Answer: Separate Steps: Claim & Prove
◍ JSON. Answer: Key Value Pairs
- { "name" : "MikeMcMac1" }
- between curly braces
◍ Measures & Dimensions. Answer: Measures - Data observed &
explored
Dimensions - Space & Time segment data
◍ Non-Relational Databases. Answer: Developed to handle large sets
of data that are not easily organized into tables, columns, and rows
Efficient by reducing overhead via Key/Value Pairs
◍ Record Subsets & Temp Table. Answer: Record Subsets - few
records returned from larger dataset, for less waiting during command
creating/testing. Ex: First 100
,Temp Table - table not kept outside of session, for running stats on it
during that session
◍ Query Execution Plan. Answer: declarative - what to do: sequence
of steps for how to run query, with speed varying based on optimizing
via human or DBMS
◍ Correlation Coefficient. Answer: a statistical index of the
relationship between two things (from -1 to +1), computed via
statistical apps
◍ Sample. Answer: random subset of population that is representative
of population
◍ Sample Standard Deviation. Answer: sum of [ (sample value minus
sample average) squared] divided by numbers of samples less one.
used as approximation of population standard deviation
◍ T-Test. Answer: Compares mean values of a continuous variable
between 2 categories/groups.
◍ Chi-Square Test. Answer: hypothesis testing method for whether
your data is as expected.
If you have a single measurement variable, you use a Chi-square
goodness of fit test. If you have two measurement variables, you use a
Chi-square test of independence.
, ◍ XML. Answer: Structured text all in <>
◍ Online transactional processing (OLTP). Answer: live capture of
transaction and event info to:
1) process info according to defined business rules
2) store info
3) update existing info if changed
Typically, OLTP databases are in 3NF.
◍ Online analytical processing (OLAP). Answer: using queries to
investigate, analyze, & report hypothesized relationships among
stored data
databases that power OLAP systems have a denormalized design.
Instead of having data distributed across multiple tables,
denormalization results in wider tables than those found in an OLTP
database. It is more efficient for analytical queries to read large
amounts of data for a single table instead of incurring the cost of
joining multiple tables together.
◍ Extract, transform, load (ETL). Answer: The process by which raw
data is extracted from various sources, transformed into a format to
support the analysis to be performed, and loaded into the data
warehouse.
EVALUATION EXAM Q&A: 2026 STUDY GUIDE
100% CORRECT
◍ HTML. Answer: Formatting tags in <>
◍ Ident & Auth. Answer: Separate Steps: Claim & Prove
◍ JSON. Answer: Key Value Pairs
- { "name" : "MikeMcMac1" }
- between curly braces
◍ Measures & Dimensions. Answer: Measures - Data observed &
explored
Dimensions - Space & Time segment data
◍ Non-Relational Databases. Answer: Developed to handle large sets
of data that are not easily organized into tables, columns, and rows
Efficient by reducing overhead via Key/Value Pairs
◍ Record Subsets & Temp Table. Answer: Record Subsets - few
records returned from larger dataset, for less waiting during command
creating/testing. Ex: First 100
,Temp Table - table not kept outside of session, for running stats on it
during that session
◍ Query Execution Plan. Answer: declarative - what to do: sequence
of steps for how to run query, with speed varying based on optimizing
via human or DBMS
◍ Correlation Coefficient. Answer: a statistical index of the
relationship between two things (from -1 to +1), computed via
statistical apps
◍ Sample. Answer: random subset of population that is representative
of population
◍ Sample Standard Deviation. Answer: sum of [ (sample value minus
sample average) squared] divided by numbers of samples less one.
used as approximation of population standard deviation
◍ T-Test. Answer: Compares mean values of a continuous variable
between 2 categories/groups.
◍ Chi-Square Test. Answer: hypothesis testing method for whether
your data is as expected.
If you have a single measurement variable, you use a Chi-square
goodness of fit test. If you have two measurement variables, you use a
Chi-square test of independence.
, ◍ XML. Answer: Structured text all in <>
◍ Online transactional processing (OLTP). Answer: live capture of
transaction and event info to:
1) process info according to defined business rules
2) store info
3) update existing info if changed
Typically, OLTP databases are in 3NF.
◍ Online analytical processing (OLAP). Answer: using queries to
investigate, analyze, & report hypothesized relationships among
stored data
databases that power OLAP systems have a denormalized design.
Instead of having data distributed across multiple tables,
denormalization results in wider tables than those found in an OLTP
database. It is more efficient for analytical queries to read large
amounts of data for a single table instead of incurring the cost of
joining multiple tables together.
◍ Extract, transform, load (ETL). Answer: The process by which raw
data is extracted from various sources, transformed into a format to
support the analysis to be performed, and loaded into the data
warehouse.
