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  • EVENT: 10060 dump predicates in optimizer (kko)

    Event:10060
    Text:   dump predicates in optimizer (kko)
    -------------------------------------------------------------------------------
    
    Explanation:
            This is a special EVENT code.
            It should *NOT* be used unless explicitly requested by ST support.
    
            This event can be useful in conjunction with an explain plan
            to confirm which operations occur where in the execution plan.
            It dumps the predicates into a special table.
    
    Usage:
            - Available in 7.1.3 onwards when using CBO
            - NOTE: This does NOT do anything under RULE
    
            - After 7.1.3 you must create a special table called
              "kkoipt_table" before you set the event. This table should be
              in the schema of the person running under event 10060.
        
                create table kkoipt_table (
                        c1 integer, c2 varchar2(80)
                );            
    
            - To enable tracing:
                ALTER session set events '10060 trace name context forever';
    
            - Run the statement to be traced
    
            - Set formatting:
              set pages 999
              column c1 format 990
              column c2 format a75
    
            - select * from KKOIPT_TABLE;
    
            - Best used in conjunction with <Event:10053> trace and an
              execution plan.
    
    
    KKOIPT_TABLE.C2 output information
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    fptconst                      - Folding constants
    fptrnum                       - Remove rownum predicates
    fptwhr                        - Remove all where predicates except remaining
                                    rownum predicates
    frofkks (rowid lookup)        - Rowid Lookup
    frofkks[i] (and-equal lookup) - Start Key (And-Equal)
    frofkke[i] (and-equal lookup) - End Key   (And-Equal)
    froiand                       - Index only predicate
    frofkksm[i] (sort-merge)      - Sort-Merg Key
    frosand (sort-merge)          - Sort-Merge Predicates
    frojand (sort-merge)          - Join Predicates
    frofkks[i] (index start key)  - Index Start Key
    frofkke[i] (index stop key)   - Index End Key
    frofand (hash part)           - Table Predicate (Hash)
    froiand (index only filter)   - Index Only Predicate
    frofand                       - Table Predicate
    froutand                      - Outer Join Predicates
    
    Example:
    ~~~~~~~
    select a.* from memp a, memp b
    where a.sal > 5050 and rownum < 4 and 1=1
      and a.empno (+) = b.empno;
    
    Output: (from kkoipt_table)
    
             1 fptrnum
             2  4>ROWNUM
             3 Table:
             4 MEMP
             5 frofand
             6  "A"."SAL">5050
             7 Table:
             8 MEMP
             9 frofand
            10  "A"."EMPNO"="B"."EMPNO"
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  • 原文地址:https://www.cnblogs.com/macleanoracle/p/2967231.html
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