A key part specification. More...

#include <parse_tree_nodes.h>

Inheritance diagram for PT_key_part_specification:

Public Member Functions
	PT_key_part_specification (Item *expression, enum_order order)
	Constructor for a functional key part. More...

	PT_key_part_specification (const LEX_CSTRING &column_name, enum_order order, int prefix_length)
	Constructor for a "normal" key part. More...

bool	contextualize (Parse_context *pc) override
	Contextualize this key part specification. More...

Item *	get_expression () const
	Get the indexed expression. More...

enum_order	get_order () const

bool	is_explicit () const

bool	has_expression () const

LEX_CSTRING	get_column_name () const
	Get the column that this key part points to. More...

int	get_prefix_length () const

Public Member Functions inherited from Parse_tree_node_tmpl< Context >
virtual	~Parse_tree_node_tmpl ()=default

bool	is_contextualized () const

virtual bool	contextualize (Context *pc)
	Do all context-sensitive things and mark the node as contextualized. More...

void	error (Context *pc, const POS &pos) const
	syntax_error() function replacement for deferred reporting of syntax errors More...

void	error (Context pc, const POS &pos, const char msg) const
	syntax_error() function replacement for deferred reporting of syntax errors More...

void	errorf (Context pc, const POS &pos, const char format,...) const
	syntax_error() function replacement for deferred reporting of syntax errors More...

Private Types
typedef Parse_tree_node	super

Private Attributes
Item *	m_expression
	The indexed expression in case this is a functional key part. More...

enum_order	m_order
	The direction of the index. More...

LEX_CSTRING	m_column_name
	The name of the column that this key part indexes. More...

int	m_prefix_length
	If this is greater than zero, it represents how many bytes of the column that is indexed. More...

Additional Inherited Members
Public Types inherited from Parse_tree_node_tmpl< Context >
typedef Context	context_t

Static Public Member Functions inherited from Parse_tree_node_tmpl< Context >
static void *	operator new (size_t size, MEM_ROOT *mem_root, const std::nothrow_t &arg=std::nothrow) noexcept

static void	operator delete (void *ptr, size_t size)

static void	operator delete (void , MEM_ROOT , const std::nothrow_t &) noexcept

Protected Member Functions inherited from Parse_tree_node_tmpl< Context >
	Parse_tree_node_tmpl ()

Detailed Description

A key part specification.

This can either be a "normal" key part (a key part that points to a column), or this can be a functional key part (a key part that points to an expression).

Member Typedef Documentation

◆ super

typedef Parse_tree_node PT_key_part_specification::super

private

Constructor & Destructor Documentation

◆ PT_key_part_specification() [1/2]

PT_key_part_specification::PT_key_part_specification	(	Item *	expression,
		enum_order	order
	)

Constructor for a functional key part.

Parameters

expression	The expression to index.
order	The direction of the index.

◆ PT_key_part_specification() [2/2]

PT_key_part_specification::PT_key_part_specification	(	const LEX_CSTRING &	column_name,
		enum_order	order,
		int	prefix_length
	)

Constructor for a "normal" key part.

That is a key part that points to a column and not an expression.

Parameters

column_name	The column name that this key part points to.
order	The direction of the index.
prefix_length	How many bytes or characters this key part should index, or zero if it should index the entire column.

Member Function Documentation

◆ contextualize()

bool PT_key_part_specification::contextualize ( Parse_context * pc )

override

Contextualize this key part specification.

This will also call itemize on the indexed expression if this is a functional key part.

Parameters

pc	The parse context

Return values

true	on error
false	on success

◆ get_column_name()

LEX_CSTRING PT_key_part_specification::get_column_name ( ) const

inline

Get the column that this key part points to.

This is only valid if this key part isn't a functional index. The caller must thus check the return value of has_expression() before calling this function.

Returns: The column that this key part points to.

◆ get_expression()

Item * PT_key_part_specification::get_expression ( ) const

inline

Get the indexed expression.

The caller must ensure that has_expression() returns true before calling this.

Returns: The indexed expression

◆ get_order()

enum_order PT_key_part_specification::get_order ( ) const

inline

Returns: The direction of the index: ORDER_ASC, ORDER_DESC or ORDER_NOT_RELEVANT in case the user didn't explicitly specify a direction.

◆ get_prefix_length()

int PT_key_part_specification::get_prefix_length ( ) const

inline

Returns: The number of bytes that this key part should index. If the column this key part points to is a non-binary column, this is the number of characters. Returns zero if the entire column should be indexed.

◆ has_expression()

bool PT_key_part_specification::has_expression ( ) const

inline

Return values

true	if the key part contains an expression (and thus is a functional key part).
false	if the key part doesn't contain an expression.

◆ is_explicit()

bool PT_key_part_specification::is_explicit ( ) const

inline

Return values

true	if the user explicitly specified a direction (asc/desc).
false	if the user didn't explicitly specify a direction.

Member Data Documentation

◆ m_column_name

LEX_CSTRING PT_key_part_specification::m_column_name

private

The name of the column that this key part indexes.

◆ m_expression

Item* PT_key_part_specification::m_expression

private

The indexed expression in case this is a functional key part.

Only valid if has_expression() returns true.

◆ m_order

enum_order PT_key_part_specification::m_order

private

The direction of the index.

◆ m_prefix_length

int PT_key_part_specification::m_prefix_length

private

If this is greater than zero, it represents how many bytes of the column that is indexed.

Note that for non-binary columns (VARCHAR, TEXT etc), this is the number of characters.

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

sql/parse_tree_nodes.h
sql/parse_tree_nodes.cc

Public Member Functions

Private Types

Private Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ super

Constructor & Destructor Documentation

◆ PT_key_part_specification() [1/2]

◆ PT_key_part_specification() [2/2]

Member Function Documentation

◆ contextualize()

◆ get_column_name()

◆ get_expression()

◆ get_order()

◆ get_prefix_length()

◆ has_expression()

◆ is_explicit()

Member Data Documentation

◆ m_column_name

◆ m_expression

◆ m_order

◆ m_prefix_length