2020-03-13

ORA-12840


Doc ID 2289797.1
parallel_max_servers=0
alter session disable parallel dml;
alter session disable parallel query;
alter session disable parallel ddl;
Session altered.

Although parallel_max_servers=0, there was an append hint used in an insert statement called from a trigger

SOLUTION

Remove  /*+ APPEND*/ in any insert statements in the package or any trigger that gets executed when the package / procedure gets called.

2020-02-23

mad world lyrics

All around me are familiar faces Worn out places, worn out faces Bright and early for the daily races Going nowhere, going nowhere Their tears are filling up their glasses No expression, no expression Hide my head I wanna drown my sorrow No tomorrow, no tomorrow And I find it kind of funny, I find it kind of sad The dreams in which I'm dying are the best I've ever had I find it hard to tell you, I find it hard to take When people run in circles its a very, very Mad world, mad world Children waiting for the day they feel good Happy birthday, happy birthday And I feel the way that every child should Sit and listen, sit and listen Went to school and I was very nervous No one knew me, no one knew me Hello teacher tell me, what's my lesson? Look right through me, look right through me And I find it kind of funny, I find it kind of sad The dreams in which I'm dying are the best I've ever had I find it hard to tell you, I find it hard to take When people run in circles its a very, very Mad world, mad world, enlarging your world Mad world

2020-02-20

black box thinking

https://archive.org/stream/BlackBoxThinkingByMatthewSyed/Black%20Box%20Thinking%20by%20Matthew%20Syed_djvu.txt

"a failure to learn from mistakes
has been one of the single greatest obstacles to human progress"

2020-01-28

decode tetra



https://www.rtl-sdr.com/rtl-sdr-tutorial-listening-tetra-radio-channels/

clickhouse storage tiers

https://www.altinity.com/blog/2019/11/27/amplifying-clickhouse-capacity-with-multi-volume-storage-part-1

multi-volume storage is a feature of ClickHouse starting in version 19.15
The idea is that you store new data on fast storage, like NVMe SSD, and move it later to slower storage, such as high-density disk. Not only does this save on storage, but you can often reduce the overall number of servers without giving up performance.  It’s a double win for efficiency that can reduce hardware costs up to 80% as this example spreadsheet shows. Not surprisingly tiered storage has been a top feature request for years.

uv-82

https://www.airsoft-cluj.ro/pub/media/UV-82-Manual-Utilizare.pdf

2020-01-07

hadoop is not dead

https://tech.marksblogg.com/is-hadoop-dead.html

When you hear "No one needs big data", look over the CV of the speaker. An African telecoms carrier going through amazing levels of growth is not going to reach out to a greenfield JavaScript Web Developer and ask them if they could help architect their data platform and optimise their billing calculations. You might find a lot of internally-hosted web applications in an Airline's headquarters but when it comes to analysing PBs of aircraft telemetry for predictive maintenance there might not be any PHP developers on that project.

Companies producing PBs of data often have a queue of experienced consultants and solutions providers at their door. I've rarely seen anyone plucked out of web development by their employer and brought into the data platform engineering space; it's almost always a lengthy, self-retraining exercise.


Disks are catching up in speeds as well. There was a 4 x 2 TB PCIe 4.0 NVMe SSD card announced recently that could read and write at 15 GB/s. The price point of the PCIe 4.0 NVMe drives will be very competitive with RAM and provide non-volatile storage. I can't wait to see an HDFS cluster with some good networking using those drives as it'll demonstrate what an in-memory data store with non-volatile storage with the rich, existing tooling of the Hadoop ecosystem looks like.



The migration to a columnar storage solution for this client brought down those infrastructure costs by two orders-of-magnitude and sped up querying times by two orders-of-magnitude.