Array Fetch Page
Array processing is the Oracle feature that enables multiple rows in a table to be returned in a single fetch.
To open the Array Fetch page
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Select the Spotlight on Oracle RAC connection in the Spotlight Browser.
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Click SQL & Application Workload | Array Fetch.
Charts on the Array Fetch Page
| Chart | Description |
|---|---|
| Array Utilization |
Array Utilization shows the average number of rows associated with each SQL statement execution with the number of rows associated with each SQL*NET round trip. If the number of rows per execution is high, but the number of rows in each network round trip is low, the application is probably failing to take advantage of array processing. |
| Call / Trip Rates |
Call/Trip Rates shows the rate at which rows are fetched compared with the rates of SQL statement executions and network round trips. If the rate of rows compared to the rate of SQL executions is high but the rate of rows compared to the rate of network round trips is low, the application is probably failing to take advantage of array processing. |
The Array Fetch SQL statements grid
Array Fetch SQL Statements lists SQL statements that may be associated with low array fetch rates. This is based on a comparison of the number of rows fetched per execution with the number of specific fetch calls issued by the SQL.
"Wastage" is a measure of the approximate overhead incurred by a low array size. It is defined as:
rows_processed*(ROUND (LEAST ( ROUND (rows_processed / fetches, 2) / LEAST (rows_processed / executions, 10),1),2) )
| Column | Description |
|---|---|
|
ID |
The SQL identifier of the SQL statement being executed. |
|
Child Number |
The number of the cursor (if any) that is a child of the cursor that contains the SQL statement. |
|
Wastage |
Overhead incurred by a low array size. |
| Rows | The total number of rows processed by this SQL statement. |
|
Rows/Exec |
The average rate at which rows are processed per execution. |
|
Rows/Fetch |
The average rate at which rows are processed per fetch. |
|
Buffer Gets |
The number of logical reads (buffer gets) retrieved by the SQL statement. |
|
Disk Reads |
The number of physical disk reads recorded against this SQL statement. |
| Executions | The number of times the SQL statement has been executed. |
| Fetches | The number of row fetch operations in the session |
|
CPU Time |
The amount of CPU time spent fetching rows and executing the SQL statement. |
|
Elapsed Time |
The total amount of time taken to fetch rows and execute the SQL statement. |
|
SQL Text |
The text of the SQL statement. |