| # | Name | Goal | Type | Data source ▲ | Last update | License | |
|---|---|---|---|---|---|---|---|
| 241 | At most one row is permitted in a table (based on enumeration types) | Find base tables and foreign tables where based on the type of a column, a key constraint, and a NOT NULL constraint can be at most one row. Make sure that this is the real intent behind the constraint, not a mistake. Find tables where a column has an enumeration type with exactly one value, the column has NOT NULL constraint, and constitutes a key, i.e., has the PRIMARY KEY or UNIQUE constraint. | General | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 242 | Avoid using length function | This query identifies all expressions that use the non-standard length() function. Although length() is a functional synonym for char_length() in PostgreSQL, its use is discouraged for two primary reasons: char_length() is the SQL-standard function, and length() has different semantics in other database systems (e.g., returning byte length in MySQL). To enhance code portability and prevent semantic ambiguity for developers, this query flags all instances of length() to encourage standardization on the char_length() function. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-13 12:53 | MIT License | View |
| 243 | Base table column of personal names does not restrict the maximum character length | This query identifies base table columns that, based on their name, are presumed to store personal names but lack an explicit maximum length constraint. It operates on a heuristic, flagging columns with names like first_name, surname, etc., that are defined with unbounded textual types (e.g., text, varchar) and have no corresponding CHECK constraint to limit their length (e.g., char_length(col) <= n). The absence of such a limit is a design flaw that can introduce usability issues in front-end applications and create potential security vulnerabilities related to excessive data submission. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-13 13:04 | MIT License | View |
| 244 | Base table column of surrogate key values does not have an integer data type (based on column names) | Find base table columns that belong to a primary key, unique, or foreign key constraint and that name refers to the possibility that these are used to hold surrogate key values. Find the columns where the data type of the column is not an integer type or uuid. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 245 | Base table columns permitting e-mail addresses without @ sign | Find non-foreign key base table columns that name refers to the possibility that these are used to register e-mail addresses. Find the columns that do not have any simple CHECK constraint that contains @ sign. A simple check constraint covers a single column. In this case registration of e-mail addresses without @ is most probably not prohibited. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 246 | Base table columns permitting empty strings and strings that consist of only whitespace characters (2) | This query identifies non-foreign key columns with a textual data type that lack essential validation. It specifically targets columns that are missing both of the following fundamental checks:
The absence of such comprehensive validation increases the risk of poor data quality and potential application-level bugs. |
Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-20 12:20 | MIT License | View |
| 247 | Base table columns permitting negative prices/quantity | Find non-foreign key base table columns that name refers to the possibility that these are used to register prices/quantities. Find the columns that do not have any simple CHECK constraints, i.e., a constraint that covers only this column. In this case registration of negative price/quantity is most probably not prohibited. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 248 | Base table columns permitting temporal values that may be outside the range of logical values | Find base tables columns with temporal types (date and timestamp) that do not belong to a foreign key and that do not have any associated simple CHECK constraints, i.e., constraint that involves only one column. For instance, in the column registration_time that does not have any associated CHECK constraints could be values '1200-01-01 00:00' or '5900-12-31 00:00'. Rows with these values most probably represent wrong propositions and the system should restrict registration of such data. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 249 | Base table columns permitting URLs without a protocol | Find non-foreign key base table columns that name refers to the possibility that these are used to register URLs. Find the columns that do not have any simple CHECK constraint that references to a protocol. A simple check constraint covers a single column. In this case registration of URLs without a protocol is most probably not prohibited. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 250 | Base table columns that lack any simple CHECK, i.e, permit empty strings and strings that consist of only whitespace characters | This query identifies non-foreign key columns of base tables with a textual data type that lack any simple (single-column) CHECK constraint. The absence of such constraints indicates a complete lack of column-level validation, creating a risk of low-quality data ingress, including the implicit allowance of empty or whitespace-only strings. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-09 10:23 | MIT License | View |
| 251 | Base table columns with an array type | Find base table columns with an array type. Think through as to whether a column with an array type could be replaced with a separate table. | General | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 252 | Base table FILLFACTOR is not 100 | This query generates a list of all base tables where the FILLFACTOR has been explicitly set to a value other than the default of 100. This non-default setting is a deliberate performance tuning decision, intended to reserve free space within table pages to improve the efficiency of UPDATE operations by facilitating HOT updates. The query provides a comprehensive list for administrators to audit these customizations and verify that they are still necessary and appropriate for the current table workload. | General | INFORMATION_SCHEMA+system catalog base tables | 2025-11-10 09:20 | MIT License | View |
| 253 | Base table has a national identification number as a key | Find base table columns that name refers to the possibility that these are used to register national identification numbers (personal codes). Find the columns that constitute a key of a table. This in turn enforces a (restrictive) business rule that all persons of interest come from one country. Make sure that the enforced constraint is valid, i.e., there is indeed such rule in the domain. | General | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 254 | Base tables and foreign tables that do not have any CHECK constraints on non-foreign key columns | Identify possibly missing CHECK constraints. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 255 | Base tables and materialized views without any index | Find base tables and materialized views that do not have any index. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 256 | Base tables that have a surrogate key and all its unique constraints have an optional column | A surrogate key is a primary key that consist of one column. The values of this column do not have any meaning for the user and the system usually generates the values (integers) automatically. In case of defining a surrogate key in a table it is a common mistake to forget declaring existing natural keys in the table. If a key covers an optional column then it does not prevent duplicate rows where some values are missing and other values are equal. Because NULL is not a value and is not duplicate of another NULL the, follwing is possible: CREATE TABLE Uniq(a INTEGER NOT NULL, b INTEGER, CONSTRAINT ak_uniq UNIQUE (a, b)); INSERT INTO Uniq(a, b) VALUES (1, NULL); INSERT INTO Uniq(a, b) VALUES (1, NULL); |
Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 257 | Base tables that have a surrogate key and do not have any uniqueness constraints | This query identifies tables that use a single-column surrogate primary key but lack any other UNIQUE constraints or unique indexes. The absence of additional unique constraints suggests that the natural business key has not been enforced, creating a risk of data duplication that violates business rules. Tables consisting of only a single column are excluded from this check. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 15:29 | MIT License | View |
| 258 | Base tables that have no uniqueness requirement for rows whatsoever | Find base tables without any unique constraints and primary key as well as any unique index, whether it is created explicitly by a developer or automatically by the DBMS. The only legitimate reason of such a table is if it is an abstract table that is used to define common columns of subtables. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 259 | Base tables where all the unique columns are optional | Find the base tables where all the unique columns are optional. In such tables there can be rows without values that identify these rows. In this case there can be rows in the table where the values that should identify the row are missing. | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |
| 260 | Base tables where uniqueness is achieved by using only unique indexes | Find base tables where uniqueness is achieved by using only unique indexes, i.e., there is at least one unique index but no uniqueness constraints (PRIMARY KEY, UNIQUE, EXCLUDE) | Problem detection | INFORMATION_SCHEMA+system catalog base tables | 2025-11-07 10:11 | MIT License | View |