MySQL  8.0.19
Source Code Documentation
sp_instr_jump_case_when Class Reference

sp_instr_jump_case_when instruction is used in the "simple CASE" implementation. More...

#include <sp_instr.h>

Inheritance diagram for sp_instr_jump_case_when:
sp_lex_branch_instr sp_lex_instr sp_branch_instr sp_instr sp_printable

Public Member Functions

 sp_instr_jump_case_when (uint ip, LEX *lex, int case_expr_id, Item *when_expr_item, LEX_CSTRING when_expr_query)
 
virtual void print (const THD *thd, String *str)
 
virtual bool exec_core (THD *thd, uint *nextp)
 Execute core function of instruction after all preparations (e.g. More...
 
virtual void invalidate ()
 Invalidate the object. More...
 
virtual bool on_after_expr_parsing (THD *thd)
 Build CASE-expression item tree: Item_func_eq(case-expression, when-i-expression) More...
 
virtual PSI_statement_infoget_psi_info ()
 
- Public Member Functions inherited from sp_lex_branch_instr
void set_cont_dest (uint cont_dest)
 
virtual uint opt_mark (sp_head *sp, List< sp_instr > *leads)
 Mark this instruction as reachable during optimization and return the index to the next instruction. More...
 
virtual void opt_move (uint dst, List< sp_branch_instr > *ibp)
 Inform the instruction that it has been moved during optimization. More...
 
virtual uint get_cont_dest () const
 Get the continuation destination (instruction pointer for the CONTINUE HANDLER) of this instruction. More...
 
virtual bool is_invalid () const
 
virtual LEX_CSTRING get_expr_query () const
 
virtual void set_destination (uint old_dest, uint new_dest)
 Update the destination; used by the SP-instruction-optimizer. More...
 
virtual void backpatch (uint dest)
 Update all instruction with the given label in the backpatch list to the specified instruction pointer. More...
 
- Public Member Functions inherited from sp_lex_instr
 sp_lex_instr (uint ip, sp_pcontext *ctx, LEX *lex, bool is_lex_owner)
 
virtual ~sp_lex_instr ()
 
bool validate_lex_and_execute_core (THD *thd, uint *nextp, bool open_tables)
 Make a few attempts to execute the instruction. More...
 
virtual SQL_I_List< Item_trigger_field > * get_instr_trig_field_list ()
 
virtual bool execute (THD *thd, uint *nextp)
 Execute this instruction. More...
 
- Public Member Functions inherited from sp_instr
 sp_instr (uint ip, sp_pcontext *ctx)
 
virtual ~sp_instr ()
 
uint get_ip () const
 
sp_pcontextget_parsing_ctx () const
 
virtual uint opt_shortcut_jump (sp_head *, sp_instr *start)
 Short-cut jumps to jumps during optimization. More...
 
bool opt_is_marked () const
 
- Public Member Functions inherited from sp_printable
virtual ~sp_printable ()
 
- Public Member Functions inherited from sp_branch_instr
virtual ~sp_branch_instr ()
 

Static Public Attributes

static PSI_statement_info psi_info
 

Private Attributes

int m_case_expr_id
 Identifier (index) of the CASE-expression in the runtime context. More...
 
Item_case_exprm_case_expr_item
 Item representing the CASE-expression. More...
 
Itemm_eq_item
 Item corresponding to the main item of the jump-condition-expression: it's the equal function (=) in the (case-expression = when-i-expression) expression. More...
 

Additional Inherited Members

- Public Attributes inherited from sp_instr
Query_arena m_arena
 
- Protected Member Functions inherited from sp_lex_branch_instr
 sp_lex_branch_instr (uint ip, sp_pcontext *ctx, LEX *lex, Item *expr_item, LEX_CSTRING expr_query)
 
 sp_lex_branch_instr (uint ip, sp_pcontext *ctx, LEX *lex, Item *expr_item, LEX_CSTRING expr_query, uint dest)
 
- Protected Member Functions inherited from sp_lex_instr
virtual void get_query (String *sql_query) const
 Return the query string, which can be passed to the parser. More...
 
virtual void cleanup_before_parsing (THD *thd)
 Destroy items in the free list before re-parsing the statement query string (and thus, creating new items). More...
 
- Protected Member Functions inherited from sp_instr
void clear_da (THD *thd) const
 Clear diagnostics area. More...
 
- Protected Attributes inherited from sp_lex_branch_instr
uint m_dest
 Where we will go. More...
 
uint m_cont_dest
 Where continue handlers will go. More...
 
sp_instrm_optdest
 
sp_instrm_cont_optdest
 
Itemm_expr_item
 Expression item. More...
 
LEX_CSTRING m_expr_query
 SQL-query corresponding to the expression. More...
 
- Protected Attributes inherited from sp_lex_instr
LEXm_lex
 LEX-object. More...
 
- Protected Attributes inherited from sp_instr
bool m_marked
 Show if this instruction is reachable within the SP (used by SP-optimizer). More...
 
uint m_ip
 Instruction pointer. More...
 
sp_pcontextm_parsing_ctx
 Instruction parsing context. More...
 

Detailed Description

sp_instr_jump_case_when instruction is used in the "simple CASE" implementation.

It's a jump instruction with the following condition: (CASE-expression = WHEN-expression) CASE-expression is retrieved from sp_rcontext; WHEN-expression is kept by this instruction.

Constructor & Destructor Documentation

◆ sp_instr_jump_case_when()

sp_instr_jump_case_when::sp_instr_jump_case_when ( uint  ip,
LEX lex,
int  case_expr_id,
Item when_expr_item,
LEX_CSTRING  when_expr_query 
)
inline

Member Function Documentation

◆ exec_core()

bool sp_instr_jump_case_when::exec_core ( THD thd,
uint nextp 
)
virtual

Execute core function of instruction after all preparations (e.g.

setting of proper LEX, saving part of the thread context).

Parameters
thdThread context.
[out]nextpnext instruction pointer
Returns
Error flag.

Implements sp_lex_instr.

◆ get_psi_info()

virtual PSI_statement_info* sp_instr_jump_case_when::get_psi_info ( )
inlinevirtual

Implements sp_instr.

◆ invalidate()

virtual void sp_instr_jump_case_when::invalidate ( )
inlinevirtual

Invalidate the object.

Reimplemented from sp_lex_branch_instr.

◆ on_after_expr_parsing()

bool sp_instr_jump_case_when::on_after_expr_parsing ( THD thd)
virtual

Build CASE-expression item tree: Item_func_eq(case-expression, when-i-expression)

This function is used for the following form of CASE statement: CASE case-expression WHEN when-1-expression THEN ... WHEN when-2-expression THEN ... ... WHEN when-n-expression THEN ... END CASE

The thing is that after the parsing we have an item (item tree) for the case-expression and for each when-expression. Here we build jump conditions: expressions like (case-expression = when-i-expression).

Parameters
thdThread context.
Returns
Error flag.

Reimplemented from sp_lex_instr.

◆ print()

void sp_instr_jump_case_when::print ( const THD thd,
String str 
)
virtual

Implements sp_printable.

Member Data Documentation

◆ m_case_expr_id

int sp_instr_jump_case_when::m_case_expr_id
private

Identifier (index) of the CASE-expression in the runtime context.

◆ m_case_expr_item

Item_case_expr* sp_instr_jump_case_when::m_case_expr_item
private

Item representing the CASE-expression.

◆ m_eq_item

Item* sp_instr_jump_case_when::m_eq_item
private

Item corresponding to the main item of the jump-condition-expression: it's the equal function (=) in the (case-expression = when-i-expression) expression.

◆ psi_info

PSI_statement_info sp_instr_jump_case_when::psi_info
static
Initial value:
= {0, "jump_case_when", 0,

The documentation for this class was generated from the following files:
PSI_DOCUMENT_ME
#define PSI_DOCUMENT_ME
Definition: psi_base.h:46