MySQL  8.0.28
Source Code Documentation
Sql_cmd_delete Class Referencefinal

#include <sql_delete.h>

Inheritance diagram for Sql_cmd_delete:
Sql_cmd_dml Sql_cmd

Public Member Functions

 Sql_cmd_delete (bool multitable_arg, SQL_I_List< TABLE_LIST > *delete_tables_arg)
 
enum_sql_command sql_command_code () const override
 Return the command code for this statement. More...
 
bool is_single_table_plan () const override
 
bool accept (THD *thd, Select_lex_visitor *visitor) override
 
- Public Member Functions inherited from Sql_cmd_dml
virtual bool is_data_change_stmt () const
 
bool prepare (THD *thd) override
 Command-specific resolving (doesn't include LEX::prepare()) More...
 
bool execute (THD *thd) override
 Execute a DML statement. More...
 
bool is_dml () const override
 
virtual bool may_use_cursor () const
 
Query_resultquery_result () const
 
void set_query_result (Query_result *result)
 Set query result object for this query statement. More...
 
void set_lazy_result ()
 Signal that root result object needs preparing in next execution. More...
 
- Public Member Functions inherited from Sql_cmd
bool needs_explicit_preparation () const
 
bool is_regular () const
 
bool is_prepared () const
 
virtual void cleanup (THD *)
 Command-specific reinitialization before execution of prepared statement. More...
 
void set_owner (Prepared_statement *stmt)
 Set the owning prepared statement. More...
 
Prepared_statementowner () const
 Get the owning prepared statement. More...
 
void set_as_part_of_sp ()
 Mark statement as part of procedure. More...
 
bool is_part_of_sp () const
 
virtual const MYSQL_LEX_CSTRINGeligible_secondary_storage_engine () const
 Is this statement of a type and on a form that makes it eligible for execution in a secondary storage engine? More...
 
void disable_secondary_storage_engine ()
 Disable use of secondary storage engines in this statement. More...
 
bool secondary_storage_engine_disabled () const
 Has use of secondary storage engines been disabled for this statement? More...
 
void use_secondary_storage_engine (const handlerton *hton)
 Mark the current statement as using a secondary storage engine. More...
 
bool using_secondary_storage_engine () const
 Is this statement using a secondary storage engine? More...
 
const handlertonsecondary_engine () const
 Get the handlerton of the secondary engine that is used for executing this statement, or nullptr if a secondary engine is not used. More...
 
void set_optional_transform_prepared (bool value)
 
bool is_optional_transform_prepared ()
 

Protected Member Functions

bool precheck (THD *thd) override
 Perform a precheck of table privileges for the specific operation. More...
 
bool check_privileges (THD *thd) override
 Check privileges on a prepared statement, called at start of execution of the statement. More...
 
bool prepare_inner (THD *thd) override
 Prepare a DELETE statement. More...
 
bool execute_inner (THD *thd) override
 Execute a DELETE statement. More...
 
- Protected Member Functions inherited from Sql_cmd_dml
 Sql_cmd_dml ()
 
bool is_empty_query () const
 
void set_empty_query ()
 Set statement as returning no data. More...
 
bool check_all_table_privileges (THD *thd)
 Read and check privileges for all tables in a DML statement. More...
 
virtual bool restore_cmd_properties (THD *thd)
 Restore command properties before execution. More...
 
virtual bool save_cmd_properties (THD *thd)
 Save command properties, such as prepared query details and table props. More...
 
const MYSQL_LEX_CSTRINGget_eligible_secondary_engine () const
 Helper function that checks if the command is eligible for secondary engine and if that's true returns the name of that eligible secondary storage engine. More...
 
- Protected Member Functions inherited from Sql_cmd
 Sql_cmd ()
 
virtual ~Sql_cmd ()
 
void set_prepared ()
 Set this statement as prepared. More...
 

Private Member Functions

bool delete_from_single_table (THD *thd)
 Delete a set of rows from a single table. More...
 

Private Attributes

bool multitable
 
SQL_I_List< TABLE_LIST > * delete_tables
 References to tables that are deleted from in a multitable delete statement. More...
 

Additional Inherited Members

- Protected Attributes inherited from Sql_cmd_dml
LEXlex
 Pointer to LEX for this statement. More...
 
Query_resultresult
 Pointer to object for handling of the result. More...
 
bool m_empty_query
 True if query will produce no rows. More...
 
bool m_lazy_result
 True: prepare query result on next execution. More...
 

Constructor & Destructor Documentation

◆ Sql_cmd_delete()

Sql_cmd_delete::Sql_cmd_delete ( bool  multitable_arg,
SQL_I_List< TABLE_LIST > *  delete_tables_arg 
)
inline

Member Function Documentation

◆ accept()

bool Sql_cmd_delete::accept ( THD thd,
Select_lex_visitor visitor 
)
overridevirtual

Reimplemented from Sql_cmd.

◆ check_privileges()

bool Sql_cmd_delete::check_privileges ( THD thd)
overrideprotectedvirtual

Check privileges on a prepared statement, called at start of execution of the statement.

Check that user has all relevant privileges to the statement, ie. INSERT privilege for columns inserted into, UPDATE privilege for columns that are updated, DELETE privilege for tables that are deleted from, SELECT privilege for columns that are referenced, etc.

Parameters
thdthread handler
Returns
false if success, true if false

Implements Sql_cmd_dml.

◆ delete_from_single_table()

bool Sql_cmd_delete::delete_from_single_table ( THD thd)
private

Delete a set of rows from a single table.

Parameters
thdThread handler
Returns
false on success, true on error
Note
Like implementations of other DDL/DML in MySQL, this function relies on the caller to close the thread tables. This is done in the end of dispatch_command().

< Flag for fatal errors

read_removal is only used by NDB storage engine

◆ execute_inner()

bool Sql_cmd_delete::execute_inner ( THD thd)
overrideprotectedvirtual

Execute a DELETE statement.

Reimplemented from Sql_cmd_dml.

◆ is_single_table_plan()

bool Sql_cmd_delete::is_single_table_plan ( ) const
inlineoverridevirtual
Returns
true if implemented as single table plan, DML statement only

Reimplemented from Sql_cmd_dml.

◆ precheck()

bool Sql_cmd_delete::precheck ( THD thd)
overrideprotectedvirtual

Perform a precheck of table privileges for the specific operation.

Check that user has some relevant privileges for all tables involved in the statement, e.g. SELECT privileges for tables selected from, INSERT privileges for tables inserted into, etc. This function will also populate TABLE_LIST::grant with all privileges the user has for each table, which is later used during checking of column privileges. Note that at preparation time, views are not expanded yet. Privilege checking is thus rudimentary and must be complemented with later calls to Query_block::check_view_privileges(). The reason to call this function at such an early stage is to be able to quickly reject statements for which the user obviously has insufficient privileges. This function is called before preparing the statement. The function must also be complemented with proper privilege checks for all involved columns (e.g. check_column_grant_*).

See also
also the function comment of Query_block::prepare(). During execution of a prepared statement, call check_privileges() instead.
Parameters
thdthread handler
Returns
false if success, true if false

Implements Sql_cmd_dml.

◆ prepare_inner()

bool Sql_cmd_delete::prepare_inner ( THD thd)
overrideprotectedvirtual

Prepare a DELETE statement.

Implements Sql_cmd_dml.

◆ sql_command_code()

enum_sql_command Sql_cmd_delete::sql_command_code ( ) const
inlineoverridevirtual

Return the command code for this statement.

Implements Sql_cmd.

Member Data Documentation

◆ delete_tables

SQL_I_List<TABLE_LIST>* Sql_cmd_delete::delete_tables
private

References to tables that are deleted from in a multitable delete statement.

Only used to track such tables from the parser. In preparation and optimization, use the TABLE_LIST::updating property instead.

◆ multitable

bool Sql_cmd_delete::multitable
private

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