Oracle multiple processes updating same table Adult xxx dating for free
It is a deadlock due to user error in the design of an application or from issuing incorrect ad-hoc SQL. (All the information I requested is available in the trace file.) As Alessandro mentioned, it's possible for sessions locking different rows in the same table to deadlock due to unindexed foreign keys on the child table of a parent/child relationship.
The following information may aid in determining the deadlock: Deadlock graph: ---------Blocker(s)-------- ---------Waiter(s)--------- Resource Name process session holds waits process session holds waits TX-0007003e-0081d6c3 45 790 X 104 20 X TX-00080043-0085e6be 104 20 X 45 790 X session 790: DID 0001-002D-000035F9 session 20: DID 0001-0068-000007F6 session 20: DID 0001-0068-000007F6 session 790: DID 0001-002D-000035F9 Rows waited on: Session 790: obj - rowid = 0000F0C8 - AAAPDIAAMAAAEf IAAA (dictionary objn - 61640, file - 12, block - 18376, slot - 0) Session 20: obj - rowid = 0000F0C8 - AAAPDIAAMAAAEf GAAA (dictionary objn - 61640, file - 12, block - 18374, slot - 0) ----- Information for the OTHER waiting sessions ----- Session 20: sid: 20 ser: 4225 audsid: 57496371 user: 72/RPT_TABLE flags: (0x45) USR/- flags_idl: (0x1) BSY/-/-/-/-/- flags2: (0x40009) -/-/INC pid: 104 O/S info: user: oracle, term: UNKNOWN, ospid: 20798 image: [email protected] client details: O/S info: user: gtsgen, term: unknown, ospid: 1234 machine: caiapp08p-node0program: JDBC Thin Client application name: JDBC Thin Client, hash value=2546894660 current SQL: delete from RPT_TABLE. Also, It's possible that you could have deadlocks on two sessions updating different rows of the same table, even if the table is not part of a parent/child relationship, if, for example, the table has a shortage of ITL entries.
For this reason foreign keys should almost always be indexed.
The only exception is when the matching unique or primary key is never updated or deleted.
Impdp parallelism also allows for the simultaneous loading of PL/SQL package bodies and parallel index building (not recommended).
for large import jobs, it is often faster to drop, load the table using impdp and then rebuild the indexes.
In addition to the data, sometimes metadata is can loaded in parallel when the "parallel" clause is set to a degree greater than one.
However, parallelism can be used against a single dmp file by breaking the dmp file into equal-sized chunks and loading each into the target table(s) simultaneously.
However, a Data Pump import is dependent upon other objects, such that they must be done serially, and cannot be parallelized.
Question: I want to update multiple rows in my table, and I need to understand how to update multiple columns.
I already know how to update multiple rows using my where clause, but I don't see how to update multiple columns.