Data
Modeling
—
Hard
Skills
01
The
List
1 – 46
01
Conceptual
,
logical
,
and
physical
data
modeling
02
Entity
-
relationship
(
ER
)
modeling
03
Relational
modeling
&
normalization
(1
NF
–5
NF
,
BCNF
)
04
Dimensional
modeling
(
Kimball
star
schema
)
05
Data
Vault
2.0
modeling
06
Canonical
&
industry
reference
models
07
Key
design
(
surrogate
vs
.
natural
keys
)
08
Referential
integrity
&
constraint
design
09
Cardinality
&
optionality
analysis
10
Many
-
to
-
many
resolution
&
bridge
tables
11
Recursive
hierarchies
&
traversal
SQL
12
Slowly
changing
dimensions
(
SCD
0–7)
13
Temporal
&
bitemporal
modeling
14
Physical
storage
&
access
-
path
design
15
Index
design
&
index
selection
16
Partitioning
&
sharding
strategy
17
Denormalization
&
pre
-
aggregation
18
Query
-
plan
analysis
&
performance
tuning
19
Data
type
&
numeric
precision
selection
20
Document
modeling
(
embedding
vs
.
referencing
)
21
Key
-
value
&
wide
-
column
modeling
22
Graph
data
modeling
23
Time
-
series
modeling
24
Geospatial
&
full
-
text
search
modeling
25
Vector
&
embedding
schema
design
26
Data
warehouse
&
lakehouse
architecture
27
OLAP
&
multidimensional
modeling
28
Semantic
layer
&
metrics
modeling
29
Data
mesh
&
data
product
design
30
Master
&
reference
data
modeling
31
Event
,
streaming
&
CDC
schema
design
32
Data
profiling
&
source
reverse
engineering
33
Data
quality
rule
design
34
Metadata
management
&
data
lineage
35
Naming
conventions
&
data
dictionary
standards
36
Privacy
,
security
&
PII
-
aware
schema
design
37
Regulatory
&
retention
modeling
38
Big
data
table
formats
&
file
layout
39
Schema
evolution
&
migration
design
40
Lakehouse
partitioning
&
compaction
strategy
41
SQL
DDL
/
DML
&
advanced
analytical
SQL
42
Data
modeling
tools
&
notation
standards
43
Transformation
frameworks
(
dbt
,
Dataform
)
44
Schema
-
as
-
code
&
migration
tooling
45
Data
contract
authoring
46
Diagramming
&
documentation
tooling
1 / 6
02
What
Each
Skill
Covers
Definitions
&
scope
A
Modeling
Methods
&
Paradigms
01
Conceptual
,
logical
,
and
physical
data
modeling
—
moving
a
design
through
three
abstraction
levels
:
business
entities
and
rules
,
then
normalized
structures
,
then
DDL
with
types
,
indexes
,
and
storage
clauses
.
02
Entity
-
relationship
modeling
—
Chen
,
crow
'
s
-
foot
,
and
IDEF
1
X
notation
;
entity
discovery
,
relationship
verbs
,
cardinality
,
and
participation
constraints
.
03
Relational
modeling
&
normalization
—
1
NF
through
5
NF
and
BCNF
,
functional
and
multivalued
dependency
analysis
,
lossless
decomposition
,
and
deliberate
denormalization
.
04
Dimensional
modeling
(
Kimball
)
—
grain
declaration
,
fact
table
types
,
conformed
dimensions
,
bus
matrix
design
,
snowflaking
trade
-
offs
,
junk
,
degenerate
,
and
role
-
playing
dimensions
.
05
Data
Vault
2.0
modeling
—
hubs
,
links
,
satellites
,
hash
keys
,
raw
vault
versus
business
vault
,
and
auditable
insert
-
only
historization
.
06
Canonical
&
industry
reference
models
—
adapting
IBM
BDW
,
FSLDM
,
ACORD
,
HL
7
FHIR
,
and
TM
Forum
SID
structures
to
a
specific
enterprise
.
B
Keys
,
Relationships
&
Integrity
07
Key
design
—
surrogate
versus
natural
keys
,
composite
keys
,
candidate
and
alternate
keys
,
UUID
/
ULID
generation
,
and
hash
key
construction
.
08
Referential
integrity
&
constraint
design
—
primary
and
foreign
keys
,
unique
,
check
,
not
-
null
,
and
default
constraints
,
plus
delete
and
update
cascade
rules
.
09
Cardinality
&
optionality
analysis
—
resolving
1:1, 1:
N
,
and
M
:
N
relationships
and
documenting
minimum
and
maximum
participation
on
each
side
.
10
Many
-
to
-
many
resolution
&
bridge
tables
—
associative
entities
,
weighting
factors
,
multi
-
valued
dimension
bridging
,
and
factless
fact
tables
.
11
Recursive
hierarchies
&
traversal
SQL
—
adjacency
lists
,
path
enumeration
,
nested
sets
,
closure
tables
,
and
recursive
CTEs
for
ragged
and
variable
-
depth
trees
.
12
Slowly
changing
dimensions
(
SCD
0–7)
—
Type
1
overwrite
through
Type
6
hybrid
,
Type
7
dual
-
key
,
effective
dating
,
current
-
flag
columns
,
and
late
-
arriving
dimensions
.
13
Temporal
&
bitemporal
modeling
—
valid
time
versus
transaction
time
,
system
-
versioned
tables
,
time
-
travel
queries
,
and
as
-
of
reporting
.
2 / 6
C
Physical
Design
&
Performance
14
Physical
storage
&
access
-
path
design
—
tablespaces
and
filegroups
,
row
versus
column
store
,
page
and
row
structure
,
compression
,
and
tablespace
placement
.
15
Index
design
&
selection
—
clustered
and
nonclustered
B
-
tree
,
bitmap
,
covering
,
filtered
,
hash
,
GIN
/
GiST
,
and
composite
key
-
order
decisions
.
16
Partitioning
&
sharding
strategy
—
range
,
list
,
and
hash
partitioning
,
partition
pruning
,
distribution
keys
,
and
shard
-
key
selection
for
even
load
.
17
Denormalization
&
pre
-
aggregation
—
materialized
views
,
summary
and
rollup
tables
,
aggregate
navigation
,
and
read
-
model
projections
.
18
Query
-
plan
analysis
&
performance
tuning
—
execution
plans
,
cardinality
estimation
,
statistics
maintenance
,
join
strategy
selection
,
and
scan
-
versus
-
seek
diagnosis
.
19
Data
type
&
precision
selection
—
DECIMAL
versus
float
,
date
and
timezone
handling
,
CHAR
/
VARCHAR
sizing
,
LOB
storage
,
and
semi
-
structured
types
(
JSON
,
VARIANT
).
D
Non
-
Relational
&
Specialized
Models
20
Document
modeling
—
embedding
versus
referencing
,
aggregate
boundaries
,
bounded
array
growth
,
and
schema
versioning
in
MongoDB
-
class
stores
.
21
Key
-
value
&
wide
-
column
modeling
—
access
-
pattern
-
first
table
design
,
partition
and
clustering
keys
,
denormalized
query
tables
,
and
hot
-
partition
avoidance
in
Cassandra
and
DynamoDB
.
22
Graph
data
modeling
—
property
graph
and
RDF
triples
,
node
and
relationship
labels
,
supernodes
,
traversal
patterns
,
and
relationship
direction
choices
.
23
Time
-
series
modeling
—
tags
versus
fields
,
hypertable
and
chunk
design
,
retention
policies
,
continuous
aggregates
,
and
downsampling
tiers
.
24
Geospatial
&
full
-
text
search
modeling
—
geometry
and
geography
types
,
spatial
index
selection
,
inverted
indexes
,
analyzers
,
and
relevance
-
field
design
.
25
Vector
&
embedding
schema
design
—
vector
columns
,
dimensionality
and
metric
choices
,
approximate
-
nearest
-
neighbor
indexes
,
and
hybrid
metadata
filtering
.
3 / 6
E
Analytics
,
Warehousing
&
Lakehouse
26
Data
warehouse
&
lakehouse
architecture
—
Inmon
CIF
versus
Kimball
,
raw
and
conformed
zones
,
medallion
bronze
/
silver
/
gold
layering
,
and
lake
-
to
-
warehouse
boundaries
.
27
OLAP
&
multidimensional
modeling
—
cubes
,
MOLAP
/
ROLAP
/
HOLAP
trade
-
offs
,
aggregation
levels
,
drill
paths
,
and
attribute
hierarchies
.
28
Semantic
layer
&
metrics
modeling
—
defining
certified
metrics
,
dimensions
,
and
joins
once
so
every
BI
tool
reports
the
same
number
.
29
Data
mesh
&
data
product
design
—
domain
ownership
boundaries
,
input
and
output
ports
,
discoverable
products
,
and
federated
computational
governance
.
30
Master
&
reference
data
modeling
—
golden
record
construction
,
match
and
merge
survivorship
rules
,
cross
-
reference
tables
,
and
entity
hierarchies
.
31
Event
,
streaming
&
CDC
schema
design
—
event
envelopes
,
Kafka
key
and
partition
strategy
,
Avro
and
Protobuf
contracts
,
schema
registry
usage
,
and
idempotent
replay
.
F
Quality
,
Governance
&
Standards
32
Data
profiling
&
source
reverse
engineering
—
null
and
distinct
-
value
analysis
,
value
distribution
,
uniqueness
checks
,
functional
dependency
discovery
,
and
legacy
schema
reconstruction
.
33
Data
quality
rule
design
—
expressing
completeness
,
accuracy
,
consistency
,
and
timeliness
as
testable
declarative
constraints
.
34
Metadata
management
&
data
lineage
—
business
and
technical
metadata
,
column
-
level
lineage
,
catalog
registration
,
and
impact
analysis
for
schema
changes
.
35
Naming
conventions
&
data
dictionary
standards
—
consistent
entity
,
column
,
and
abbreviation
rules
;
documented
definitions
;
and
a
maintained
business
glossary
.
36
Privacy
,
security
&
PII
-
aware
schema
design
—
PII
classification
,
tokenization
and
masking
columns
,
row
and
column
-
level
security
,
and
encryption
boundaries
.
37
Regulatory
&
retention
modeling
—
GDPR
and
CCPA
erasure
and
retention
requirements
,
HIPAA
field
handling
,
PCI
DSS
scope
reduction
,
and
audit
trail
design
.
4 / 6
G
Big
Data
&
Modern
Storage
38
Big
data
table
formats
&
file
layout
—
Parquet
,
ORC
,
and
Avro
encoding
;
Delta
Lake
,
Apache
Iceberg
,
and
Hudi
table
semantics
;
and
predicate
pushdown
design
.
39
Schema
evolution
&
migration
design
—
expand
-
and
-
contract
migrations
,
backward
-
compatible
column
additions
,
versioned
contracts
,
and
zero
-
downtime
cutover
.
40
Lakehouse
partitioning
&
compaction
strategy
—
partition
column
choice
,
file
-
size
targeting
,
small
-
file
compaction
,
Z
-
ordering
,
and
manifest
pruning
.
H
Tooling
&
Languages
41
SQL
DDL
/
DML
&
advanced
analytical
SQL
—
CREATE
and
ALTER
statement
design
,
MERGE
upserts
,
window
functions
,
CTEs
,
and
dialect
-
specific
analytic
constructs
.
42
Data
modeling
tools
&
notation
standards
—
hands
-
on
work
in
Erwin
,
ER
/
Studio
,
PowerDesigner
,
and
SqlDBM
,
including
forward
and
reverse
engineering
.
43
Transformation
frameworks
—
dbt
and
Dataform
model
layering
,
sources
,
refs
,
incremental
materializations
,
and
Spark
DataFrame
transformations
.
44
Schema
-
as
-
code
&
migration
tooling
—
Git
-
versioned
DDL
,
Flyway
,
Liquibase
,
and
Alembic
changelogs
,
review
workflow
,
and
rollback
planning
.
45
Data
contract
authoring
—
publishing
schema
,
semantics
,
SLAs
,
and
ownership
for
a
dataset
so
producers
and
consumers
agree
before
changes
ship
.
46
Diagramming
&
documentation
tooling
—
producing
reviewable
ERDs
and
data
-
flow
diagrams
in
dbdiagram
.
io
,
draw
.
io
,
Lucidchart
,
Mermaid
,
or
PlantUML
.
5 / 6
03
Target
Proficiency
Profile
Senior
data
modeler
DOMAIN
SKILLS
TARGET
LEVEL
RANGE
Modeling
methods
&
paradigms
6
Expert
01–06
Keys
,
relationships
&
integrity
7
Expert
07–13
Physical
design
&
performance
6
Advanced
14–19
Non
-
relational
&
specialized
models
6
Advanced
20–25
Analytics
,
warehousing
&
lakehouse
6
Expert
26–31
Quality
,
governance
&
standards
6
Advanced
32–37
Big
data
&
modern
storage
3
Advanced
38–40
Tooling
&
languages
6
Expert
41–46
6 / 6