Categories

Currently the catalog has 54 active categories with at least one query.

Category name	Number of queries	Ranking based on number of queries
Naming	205	1
User-defined routines	191	2
Validity and completeness	151	3
CHECK constraints	140	4
Derived tables	123	5
Data types	121	6
Relationships between tables	114	7
Comfortability of database evolution	113	8
Comfortability of data management	101	9
Inconsistencies	99	10
Triggers and rules	94	11
Does not work in some earlier PostgreSQL version	90	12
Result quality depends on names	87	13
Uniqueness	83	14
Performance	80	15
Default value	67	16
Security	59	17
Duplication of implementation elements	54	18
Domains	49	19
Missing data	46	20
Regular expressions	31	21
Structure of base tables	31	21
Sequence generators	30	22
Data at the database physical level	25	23
Syntactics	25	23
Temporal data	25	23
Boolean data	24	24
Unused implementation elements	20	25
Database design antipatterns	19	26
Compensating actions	17	27
Field size	16	28
Table inheritance	16	28
System-defined functions	15	29
Transactions	14	30
Data at the database logical level	13	31
Distributed database	13	31
Comments	12	32
Assessment	11	33
Hierarchical data	11	33
User-defined types	11	33
Concurrency control	10	34
Fatal problems	10	34
State machine	10	34
Case sensitivity vs. case insensitivity	9	35
Classifier tables	7	36
Full text search	7	36
Stubs	7	36
TOAST	7	36
Extensions	6	37
Generated columns	6	37
Overloading	6	37
Data redundancy	3	38
Read user data	3	38
Schemas	3	38