Constraint_type_resolver Class Reference

Base class to resolve constraints type for the constraints specified in the ALTER TABLE ... DROP/ALTER CONSTRAINT operation. More...

#include <sql_constraint.h>

Inheritance diagram for Constraint_type_resolver:

Public Member Functions
	Constraint_type_resolver (Alter_info *alter_info)
virtual	~Constraint_type_resolver ()=default
virtual bool	is_type_resolution_needed () const =0
	Method to check if constraint type resolution is needed. More...
virtual bool	resolve_constraints_type (THD *thd, const TABLE *src_table, const dd::Table *dd_src_table)=0
	Method to resolve constraints type. More...

Protected Member Functions
KEY *	is_primary_or_unique_constraint (const TABLE *src_table, const char *name)
	Helper method to check if "name" type is PRIMARY or UNIQUE constraint. More...
bool	is_referential_constraint (const dd::Table *dd_src_table, const char *name)
	Helper method to check if "name" type is REFERENTIAL constraint. More...
bool	is_check_constraint (const TABLE *src_table, const char *name)
	Helper method to check if "name" type is CHECK constraint. More...

Protected Attributes
Alter_info *	m_alter_info
	Alter_info instance describing table being altered. More...

Detailed Description

Base class to resolve constraints type for the constraints specified in the ALTER TABLE ... DROP/ALTER CONSTRAINT operation.

For a constraint specified in the DROP/ALTER CONSTRAINT operations of a ALTER TABLE statement, actual constraint type is unknown. This is the class to resolve the actual constraint type (PRIMARY, UNIQUE, FOREIGN KEY or CHECK) of a constraint by name. Changes to Alter_info instance are reverted in the destructor to make operation safe for re-execution of a stored routines and prepared statements.

Constructor & Destructor Documentation

Constraint_type_resolver()

Constraint_type_resolver::Constraint_type_resolver ( Alter_info *  alter_info )

inlineexplicit

~Constraint_type_resolver()

virtual Constraint_type_resolver::~Constraint_type_resolver ( )

virtualdefault

Member Function Documentation

is_check_constraint()

bool Constraint_type_resolver::is_check_constraint ( const TABLE *  src_table, const char *  name  )

protected

Helper method to check if "name" type is CHECK constraint.

Parameters

src_table	TABLE instance of a source table.
name	Constraint name.

Return values

true	If "name" type is CHECK.
false	Otherwise.

is_primary_or_unique_constraint()

KEY * Constraint_type_resolver::is_primary_or_unique_constraint ( const TABLE *  src_table, const char *  name  )

protected

Helper method to check if "name" type is PRIMARY or UNIQUE constraint.

Parameters

src_table	TABLE instance of a source table.
name	Constraint name.

Return values

non-nullptr	Returns pointer to KEY instance if "name" is PRIMARY or UNIQUE constraint.
nullptr	Otherwise.

is_referential_constraint()

bool Constraint_type_resolver::is_referential_constraint ( const dd::Table *  dd_src_table, const char *  name  )

protected

Helper method to check if "name" type is REFERENTIAL constraint.

Parameters

dd_src_table	Data-dictionary table instance of a source table.
name	Constraint name.

Return values

true	If "name" type is REFERENTIAL.
false	Otherwise.

is_type_resolution_needed()

virtual bool Constraint_type_resolver::is_type_resolution_needed ( ) const

pure virtual

Method to check if constraint type resolution is needed.

Return values

true	if ALTER TABLE statement has DROP/ALTER CONSTRAINT operations.
false	Otherwise.

Implemented in Drop_constraint_type_resolver, and Enforce_constraint_type_resolver.

resolve_constraints_type()

virtual bool Constraint_type_resolver::resolve_constraints_type ( THD *  thd, const TABLE *  src_table, const dd::Table *  dd_src_table  )

pure virtual

Method to resolve constraints type.

Parameters

thd	Thread handle.
src_table	TABLE instance of a source table.
dd_src_table	Data-dictionary table instance of a source table.

Return values

false	Success.
true	Failure.

Implemented in Drop_constraint_type_resolver, and Enforce_constraint_type_resolver.

Member Data Documentation

m_alter_info

Alter_info* Constraint_type_resolver::m_alter_info

protected

Alter_info instance describing table being altered.

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The documentation for this class was generated from the following files:

• sql/sql_constraint.h
• sql/sql_constraint.cc