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ALL or ANY in SQL | Perfstat
https://perfstat.wordpress.com/2015/07/06/all-or-any-in-sql
Musings on Oracle Database. ALL or ANY in SQL. The other day I was studying a SQL statement that was performing poorly, when I noticed a peculiar syntax that I have not come across before :. SELECT COUNT(*) FROM customer WHERE annual spend ALL ( SELECT spend threshold FROM promotion WHERE promo name = 'Summer 2015' );. The only time I’d ever come across the keyword ALL in SQL was in UNION ALL. However, a quick check of the manual led me to the Group Comparison Conditions :. So how might these be useful?
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enq: TM – contention due to parallel DML and foreign keys | Perfstat
https://perfstat.wordpress.com/2015/01/19/enq-tm-contention-due-to-parallel-dml-and-foreign-keys
Musings on Oracle Database. Enq: TM – contention due to parallel DML and foreign keys. This is a write-up of an issue I recently posted to the OTN discussion forum ( https:/ community.oracle.com/message/12798407. I thought the associated test case was useful in demonstrating the issue, so is captured here for future reference. There were some useful replies to the OTN post, confirming my suspicions. The test was performed using Oracle Enterprise Edition 11.2.0.3.0 on Linux. Neither table is partitioned.
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Standard Edition is dead – long live Standard Edition 2 | Perfstat
https://perfstat.wordpress.com/2015/07/06/standard-edition-is-dead-long-live-standard-edition-2
Musings on Oracle Database. Standard Edition is dead – long live Standard Edition 2. Update 8th July – the plot thickens. Has been redacted to a “watch this space” note. So I guess we’ll have to watch this space…. My original blog posting from 6th July remains below. Disclaimer – these are my personal musings based on very limited information, which I’m sure will rapidly become out of date as more details emerge over the coming months. 12101 is the final release for SE and SE1. Beginning with 12.1...
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ORA-01555 Snapshot Too Old and Delayed Block Cleanout | Perfstat
https://perfstat.wordpress.com/2014/11/07/ora-01555-snapshot-too-old-and-delayed-block-cleanout
Musings on Oracle Database. ORA-01555 Snapshot Too Old and Delayed Block Cleanout. The usual explanation for ORA-01555 is that data is being changed whilst it’s being read, and there is insufficient undo to satisfy read-consistent requests. However, ORA-01555 can occur whilst querying a table whilst no other processes are touching the table. This seems counter-intuitive – why would undo be required when the table is static and unchanging? Enter Delayed Block Cleanout…. If the transaction was committed be...
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EZCONNECT without a password | Perfstat
https://perfstat.wordpress.com/2015/02/06/ezconnect-without-a-password
Musings on Oracle Database. EZCONNECT without a password. After encountering this little annoyance for the nth time, I thought I should write it up once and for all, so it is committed to my electronic memory. The EZCONNECT naming method is a handy way of connecting to an Oracle database by its service name, which avoids the need for aliases in the TNSNAMES file, or lengthy SQL*Net connection strings :. SQL connect user/password@hostname:port/service name Connected. This entry was posted in DBA. Address ...
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Joining to a pipelined table function and “left correlation” | Perfstat
https://perfstat.wordpress.com/2016/05/20/joining-to-a-pipelined-table-function-and-left-correlation
Musings on Oracle Database. Joining to a pipelined table function and “left correlation”. Oracle 11.2.0.4. A pipelined table function may be called from regular SQL using the TABLE collection expression, e.g. SELECT * FROM TABLE(my pipelined function('ABC','DEF') ;. Where ‘ABC’ and ‘DEF’ are the inputs to the function. What if you want to call the function repeatedly for several sets of inputs, e.g. testing the function for a variety of values? However, this returns the error ORA-00904: invalid identifier.
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Dan Jankowski | Perfstat
https://perfstat.wordpress.com/author/dpjankowski
Musings on Oracle Database. Author Archives: Dan Jankowski. Joining to a pipelined table function and “left correlation”. Oracle 11.2.0.4. A pipelined table function may be called from regular SQL using the TABLE collection expression, e.g. SELECT * FROM TABLE(my pipelined function('ABC','DEF') ;. Where ‘ABC’ and ‘DEF’ are the inputs to the function. What if you want to call the function repeatedly for several sets of inputs, e.g. testing the function for a variety of values? This entry was posted in SQL.