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Normalization


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Smruti said…
Hi Sir Please give me the answer

Why we use @@ symbol in oracle
or difference between @ and @@
Smruti said…
Hi Sir Please give me the answer

Why we use @@ symbol in oracle
or difference between @ and @@ ?


Please change the back ground color of the site from black to whit and letter color to white so the site is more eye catching.
Mithun Ashok said…
Hi Smruti,

Refer to the link below for the difference,

Difference between @ and @@

Problem with white text is its too flashy, so I usually use them for sql statements or to highlight some text on my site.

Nevertheless will change my sites theme completely in some time. :-)

Regards,
Mithun
baba said…
everything in the world is with some special trait
imbued
god has taught music sweet to the speechless birds
and god has sent mithun to teach sql
your teaching is multicolored,multifaceted flashing different hues
your teaching is like beacon light that is guiding students to their goal
your teaching has made a mark on everybodys heart
and people in large number enjoy your teaching
immortal are the merits of your teaching

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Linux-x86_64 Error: 28: No space left on device


This as you can see is on Linux x86 with 64 bit processor. We got this error after we changed SGA on 10gR2 database. So was sure that this is something to do with the OS.

Parameters to check for this are shmall.

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$cat /proc/sys/kernel/shmmax
53687091200

$ getconf PAGE_SIZE
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As per Oracle SHMALL should be set to the total amount of physical RAM divided by page size.

Our system has 64GB memory, so change kernel.shmall = 1024 * 1024 * 1024 * 64 / 4096 = 16777216


Once this value is calculated you can modify Linux system configuration file directly.

$ su - root
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and

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Once this is done the database was started without any problem.