The system table COMMANDSTATISTICS describes SQL statements that are stored in the command cache, and also contains statistical information on the activities of these SQL statements collected since the last time the database instance was started. The command cache contains the SQL statements and their execution plans shared by different database sessions
COMMANDSTATISTICS
CHAR(8) BYTE |
ID of the SQL statement |
|
CHAR(3) |
SQL statement generated implicitly by the database instance (YES|NO) |
|
HASHVALUE |
FIXED(10) |
Hash value |
HASHTABLESLOT |
FIXED(5) |
Slot in the hash table |
STATUS |
CHAR(10) |
Status (PREPARING | PREPARED | INVALID) |
USERNAME |
CHAR(32) |
Name of the database user |
SCHEMANAME |
CHAR(32) |
Current schema when execution plan created |
SQLMODE |
CHAR(10) |
|
ISOLATIONLEVEL |
CHAR(3) |
|
DATEFORMAT |
CHAR(50) |
|
MASSCOMMAND |
CHAR(3) |
Command can be used as an array command (YES|NO) |
STATEMENTSIZE |
FIXED(10) |
Length of the SQL statement (bytes) |
STATEMENT |
LONG |
SQL statement |
PLANSIZE |
FIXED(10) |
Memory requirements of the execution plan (bytes) |
PREPARECOUNT |
FIXED(10) |
Number of execution preparations |
REFERENCECOUNT |
FIXED(5) |
Number of database sessions for which the SQL statement has been prepared for execution |
CURRENTEXECUTECOUNT |
FIXED(5) |
Current number of executions |
EXECUTECOUNT |
FIXED(10) |
Number of executions |
PREPARETIME |
FIXED(20) |
Parse time (ms) |
EXECUTETIME |
FIXED(20) |
Total duration of executions (ms) |
AVGEXECUTETIME |
FIXED(20) |
Average execution time (ms) |
MINEXECUTETIME |
FIXED(20) |
Minimum execution time (ms) |
MAXEXECUTETIME |
FIXED(20) |
Maximum execution time (ms) |
READROWCOUNT |
FIXED(20) |
Number of rows read |
QUALIFIEDROWCOUNT |
FIXED(20) |
Number of qualified rows |
VIRTUALREADCOUNT |
FIXED(20) |
Number of reads in the data cache |
PHYSICALREADCOUNT |
FIXED(20) |
Number of reads in the data cache that triggered reads on the disk |
FETCHROWCOUNT |
FIXED(20) |
Number of rows (in the result tables generated by the SQL statement) sent to the application |
SUSPENDCOUNT |
FIXED(20) |
Number of suspends |
WAITCOUNT |
FIXED(20) |
Number of waits caused by lock collisions |