sql_cmd_dcl.h

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#ifndef SQL_CMD_DCL_INCLUDED
#define SQL_CMD_DCL_INCLUDED
 
#include "sql/sql_cmd.h"
 
/**
  A base class for DCL/ACL statements.
*/
class Sql_cmd_dcl : public Sql_cmd {
 public:
  enum enum_sql_cmd_type sql_cmd_type() const override {
    /*
      Somewhat unsurprisingly, anything sub-classed to Sql_cmd_dcl
      identifies as DCL by default.
    */
    return SQL_CMD_DCL;
  }
};
 
/**
  This is a dummy class for old-style commands whose code is in sql_parse.cc,
  not in the execute() function. This Sql_cmd sub-class presently exists
  solely to provide a correct sql_cmd_type() for the command; it does nothing
  else.
*/
class Sql_cmd_dcl_dummy final : public Sql_cmd_dcl {
 private:
  enum_sql_command my_sql_command{SQLCOM_END};
 
 public:
  void set_sql_command_code(enum_sql_command scc) {
    assert(my_sql_command == SQLCOM_END);  // ensure value was not set up yet
    my_sql_command = scc;
  }
 
  enum_sql_command sql_command_code() const override {
    assert(my_sql_command != SQLCOM_END);  // ensure value was set up
    return my_sql_command;
  }
 
  // Error: we should never get here! (see explanation above)
  bool execute(THD *thd [[maybe_unused]]) override {
    assert(false);
    return false;
  }
};
 
#endif  // SQL_CMD_DCL_INCLUDED