#include <opt_trace.h>
◆ Opt_trace_start()
Instantiate this class to start tracing a THD's actions (generally at a statement's start), and to set the "original" query (not transformed, as sent by client) for the new trace. 
Destructor will end the trace.
If in a routine's instruction, there is no "query". To be helpful to the user, we craft a query using the instruction's print(). We don't leave this to the caller, because it would be inefficient if tracing is off.
- Parameters
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    | thd_arg | the THD  | 
    | tbl | list of tables read/written by the statement.  | 
    | sql_command | SQL command being prepared or executed  | 
    | set_vars | what variables are set by this command (only used if sql_command is SQLCOM_SET_OPTION)  | 
    | query | query  | 
    | query_length | query's length  | 
    | instr | routine's instruction, if applicable; if so, 'query' and 'query_length' above are ignored  | 
    | query_charset | charset which was used to encode this query | 
  
   
- Note
 - Each sub-statement is responsible for ending the trace which it has started; this class achieves this by keeping some memory inside. 
 
 
 
◆ ~Opt_trace_start()
      
        
          | Opt_trace_start::~Opt_trace_start  | 
          ( | 
           | ) | 
           | 
        
      
 
 
◆ ctx
◆ error
  
  
      
        
          | bool Opt_trace_start::error | 
         
       
   | 
  
private   | 
  
 
whether trace start() had an error 
 
 
The documentation for this class was generated from the following files: