Table: `ndb.depenvttypes`#

Description#

Lookup table of Depositional Environment Types. Table is referenced by the CollectionUnits table.

TODO: Expand this description with: - What data does this table store? - What is the business/research purpose? - How is this data collected or generated? - Are there any important caveats or data quality issues?

Table Structure#

Schema: ndb | Table Comment: Lookup table of Depositional Environment Types. Table is referenced by the CollectionUnits table.

Statistics#

Metric	Value
Row Count	236
Total Size	64 kB
Table Size	24 kB
Indexes Size	16 kB

Relationships#

Primary Key: depenvtid

Foreign Keys:

depenvthigherid → depenvttypes.depenvtid

Referenced By:

TODO: Document which tables reference this table (will be auto-detected in validation).

Data Dictionary#

Column	Type	Nullable	Default	Constraints	Description
`depenvtid`	integer	✗	`nextval('ndb.seq_depenvttyp...`	PRIMARY KEY, FOREIGN KEY	An arbitrary Depositional Environment Type identification number.
`depenvt`	character varying(255)	✗	`-`	-	Depositional Environment.
`depenvthigherid`	integer	✗	`-`	-	The Depositional Environment Types are hierarchical. DepEnvtHigherID is the DepEnvtID of the higher ranked Depositional Environment. The following table gives some examples.
`recdatecreated`	timestamp without time zone	✗	`timezone('UTC'::text, now())`	-
`recdatemodified`	timestamp without time zone	✗	`-`	-

TODO: Review column descriptions and add comments where missing.

Usage Examples#

Example 1: Basic Selection#

-- Get recent records from depenvttypes
SELECT *
FROM depenvttypes
ORDER BY depenvtid DESC
LIMIT 10;

Purpose: Retrieve the 10 most recent records from depenvttypes

Example 2: Count Records#

-- Count total records
SELECT COUNT(*) as total_records
FROM depenvttypes;

Purpose: Get the total number of records in depenvttypes

Example 3: Filter by Date Range#

-- Get records within a date range
SELECT *
FROM depenvttypes
WHERE recdatecreated >= '2024-01-01'
  AND recdatecreated < '2025-01-01'
ORDER BY recdatecreated DESC;

Purpose: Retrieve records from depenvttypes within a specific date range

Example 4: Join with depenvttypes#

-- Join with related table
SELECT 
    t1.*,
    t2.*
FROM depenvttypes t1
INNER JOIN depenvttypes t2 
    ON t1.depenvthigherid = t2.depenvtid
LIMIT 100;

Purpose: Retrieve depenvttypes records with related data from depenvttypes

Example 5: Aggregate Data#

-- Aggregate records by depenvt
SELECT 
    depenvt,
    COUNT(*) as count
FROM depenvttypes
GROUP BY depenvt
ORDER BY count DESC
LIMIT 10;

Purpose: Count records grouped by depenvt

TODO: Add more specific examples relevant to common research questions or operational tasks.

Data Quality Notes#

TODO: Document: - Known data quality issues - Validation rules - Expected data ranges - Update frequency and mechanisms - Any ETL processes that populate this table

Maintenance#

Data Owner: TODO: Assign owner
Update Frequency: TODO: Document frequency
Last Major Schema Change: TODO: Document when schema last changed

Table: ndb.depenvttypes#