| Goal | Find implementations of state machines that use a state classifier table. |
|---|---|
| Notes | The query uses PostgreSQL system catalog tables not information_schema views in order to give precise answer even if foreign key constraints in different tables have the same name. In SQL a foreign key is an ordered set of columns that must contain at least one column. The query result preserves the order of columns in the key. The query considers both table names in English and Estonian. |
| Type | General (Overview of some aspect of the database.) |
| License | MIT (opens in new tab) |
| Data Source | system catalog only |
| SQL Query |
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Collections
This query belongs to the following collections:
Find problems about base tables
A selection of queries that return information about the data types, field sizes, default values as well as general structure of base tables. Contains all the types of queries - problem detection, software measure, and general overview
Find problems by overview
Queries that results point to different aspects of database that might have problems. A human reviewer has to decide based on the results as to whether there are problems or not .
| Name | Description |
|---|---|
| Find problems about base tables | A selection of queries that return information about the data types, field sizes, default values as well as general structure of base tables. Contains all the types of queries - problem detection, software measure, and general overview |
| Find problems by overview | Queries that results point to different aspects of database that might have problems. A human reviewer has to decide based on the results as to whether there are problems or not . |
Categories
This query is classified under the following categories:
Classifier tables
Queries of this category provide information about registration of classifiers.
Relationships between tables
Queries of this category provide information about how database tables are connected to each other and whether such connections have been explicitly defined and whether it has been done correctly.
Result quality depends on names
Queries of this category use names (for instance, column names) to try to guess the meaning of a database object. Thus, the goodness of names determines the number of false positive and false negative results.
State machine
Queries of this category provide information about registration of states of entities in a database.
| Name | Description |
|---|---|
| Classifier tables | Queries of this category provide information about registration of classifiers. |
| Relationships between tables | Queries of this category provide information about how database tables are connected to each other and whether such connections have been explicitly defined and whether it has been done correctly. |
| Result quality depends on names | Queries of this category use names (for instance, column names) to try to guess the meaning of a database object. Thus, the goodness of names determines the number of false positive and false negative results. |
| State machine | Queries of this category provide information about registration of states of entities in a database. |
Further reading and related materials:
| Reference |
|---|
| L. Silverston ja P. Agnew, „The Data Model Resource Book, Volume 3: Universal Patterns for Data Modeling,“ Chichester, John Wiley & Sons Ltd, 2009. Level 2 Status Pattern, Current Status |
| Representing the Status of the Main Entities of an Information System in SQL Databases Master Thesis, in Estonian. |