NonStop SQL/MP Reference Manual

Table Of Contents
NonStop SQL/MP Reference Manual142115
E-16
Considerations—EXPLAIN
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Query plan <n> [ : Will utilize parallel execution ]
SQL request : { Delete | Update | Select | Insert |
Insert-Select | Union of Selects }
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Plan step n [: Perform an [ [Inner|Left] Join|Union ] ]
[ Join strategy : [Nested | [Hybrid] Hash | ]
[ [Key Sequenced] Merge] Join ]
[ (The following section appears only for parallel ]
[ plans and is described under "Parallel Execution ]
[ Plan" in the text that follows the figure. ]
[ Typical lines are shown below, though the details ]
[ of section contents vary depending on the plan.) ]
[ ]
[ Each operation is performed in parallel for this step.]
[ ]
[ Each ESP [ from previous step ] will read one of ... ]
[ partition partition partition ... ]
[ The ESPs will be started in the CPU's numbered ]
[ n n n ... ]
[ Each ESP will perform a [ Hybrid ] Hash Join | ]
[ [ [Key Sequenced] Merge Join ... ]
:{Join sequence }
[ Plan Forced :{Join method } forced by user ... ]
:{Join sequence
and join method }
Characteristic :
:{ Insert }
Operation n :{ Scan }
{ Union of plan step n ... n }
Table :
[ Accessed via view : ] (Appears for a protection view)
Access type :
Lock mode :
Column processing :
Access path n :
SBB for reads :
[ Begin key pred. : ]
[ End key pred. : ]
[ MDAM predicate set: ]
[ next set: ]
Index selectivity :
Index pred. :