5. Constraints

Number of columns in primary key must not exceed the threshold

Code: NumOfPKColumnsExceed

Rule Description: The number of columns in the primary key is limited to avoid performance issues caused by complex primary keys.

Warning Level: Warning

Review Object: CREATE TABLE

Trigger Condition: The number of columns in the primary key exceeds the set threshold (e.g., 1).

Configurable: Yes

Example: The expression can be configured as 1, indicating that the primary key can have at most 1 column.

Supported Database Types: ALL

Data type restrictions for primary key columns

Code: DataTypeLimitOfPrimaryKey

Rule Description: The data types of primary key columns should be restricted, with integer types generally recommended for performance optimization.

Warning Level: Warning

Review Object: CREATE TABLE

Trigger Condition: Non-recommended data types are used for primary key columns.

Configurable: Yes

Example: The expression can be configured as unsigned int/unsigned bigint, indicating that primary key columns should use these unsigned integer types.

Supported Database Types: ALL

Auto-increment columns prohibited for primary keys

Code: IncColumn4PrimaryKeyDisallowed

Rule Description: Applying the auto-increment attribute to primary key columns is prohibited to avoid potential data integrity issues.

Warning Level: Warning

Review Object: CREATE TABLE

Trigger Condition: Primary key columns are defined as auto-increment.

Configurable: Yes

Example: The expression can be configured as unsigned int/unsigned bigint, indicating that these types are not allowed as auto-increment primary key columns.

Supported Database Types: ALL

Auto-increment columns should be used for primary keys

Code: IncColumn4PrimaryKeyRequired

Rule Description: The use of auto-increment attributes on primary keys is encouraged to simplify data insertion operations and maintain the continuity of the primary key.

Warning Level: Warning

Review Object: CREATE TABLE

Trigger Condition: The primary key is not defined as auto-increment.

Configurable: Yes

Example: The expression can be configured as unsigned int/unsigned bigint, indicating that primary keys should use these types with auto-increment attributes.

Supported Database Types: ALL

Foreign keys are prohibited

Code: ForeignKeyDisallowed

Rule Description: The creation of foreign key constraints is prohibited because foreign keys increase the complexity and performance overhead of database operations.

Warning Level: Warning

Review Object: CREATE TABLE, ALTER TABLE ADD CONSTRAINT

Trigger Condition: Foreign key constraints are added when creating or modifying a table.

Configurable: Yes

Example: The expression can be configured as 0.8, indicating that the creation of foreign keys is not allowed.

Supported Database Types: ALL

Inconsistent data types for primary and foreign keys

Code: DiffDataTypesOfRIColumns

Rule Description: The data types of primary keys and corresponding foreign keys must be consistent to ensure data integrity and consistency.

Warning Level: Warning

Review Object: CREATE TABLE, ALTER TABLE ADD CONSTRAINT

Trigger Condition: The data types of primary keys and foreign keys are inconsistent.

Configurable: Yes

Example: The expression can be configured as 0.8, indicating that the data types of primary and foreign keys must be consistent when creating or modifying a table.

Supported Database Types: ALL

CHECK constraints are prohibited

Code: CreateCheckConstraintDisallowed

Rule Description: The use of CHECK constraints is prohibited because they increase the complexity and performance overhead of database operations.

Warning Level: Warning

Review Object: ALTER TABLE ADD CONSTRAINT

Trigger Condition: CHECK constraints are added.

Configurable: No

Supported Database Types: ALL