other users?
4.17) What is an OID? What is a TID?
4.18) What is the meaning of some of the terms used in PostgreSQL?
- 4.19) Why do I get the error "FATAL: palloc failure: memory
- exhausted?"
- 4.20) How do I tell what PostgreSQL version I am running?
- 4.21) My large-object operations get invalid large obj descriptor.
+ 4.19) How do I tell what PostgreSQL version I am running?
+ 4.20) My large-object operations get invalid large obj descriptor.
Why?
- 4.22) How do I create a column that will default to the current time?
- 4.23) Why are my subqueries using IN so slow?
- 4.24) How do I perform an outer join?
+ 4.21) How do I create a column that will default to the current time?
+ 4.22) Why are my subqueries using IN so slow?
+ 4.23) How do I perform an outer join?
Extending PostgreSQL
5.1) I wrote a user-defined function. When I run it in psql, why does
it dump core?
- 5.2) What does the message "NOTICE:PortalHeapMemoryFree: 0x402251d0
- not in alloc set!" mean?
- 5.3) How can I contribute some nifty new types and functions to
+ 5.2) How can I contribute some nifty new types and functions to
PostgreSQL?
- 5.4) How do I write a C function to return a tuple?
- 5.5) I have changed a source file. Why does the recompile not see the
+ 5.3) How do I write a C function to return a tuple?
+ 5.4) I have changed a source file. Why does the recompile not see the
change?
_________________________________________________________________
A list of general database terms can be found at:
http://www.comptechnews.com/~reaster/dbdesign.html
- 4.19) Why do I get the error "FATAL: palloc failure: memory exhausted?"
-
- It is possible you have run out of virtual memory on your system, or
- your kernel has a low limit for certain resources. Try this before
- starting the postmaster:
- ulimit -d 65536
- limit datasize 64m
-
- Depending on your shell, only one of these may succeed, but it will
- set your process data segment limit much higher and perhaps allow the
- query to complete. This command applies to the current process, and
- all subprocesses created after the command is run. If you are having a
- problem with the SQL client because the backend is returning too much
- data, try it before starting the client.
-
- 4.20) How do I tell what PostgreSQL version I am running?
+ 4.19) How do I tell what PostgreSQL version I am running?
From psql, type select version();
- 4.21) My large-object operations get invalid large obj descriptor. Why?
+ 4.20) My large-object operations get invalid large obj descriptor. Why?
You need to put BEGIN WORK and COMMIT around any use of a large object
handle, that is, surrounding lo_open ... lo_close.
If you are using a client interface like ODBC you may need to set
auto-commit off.
- 4.22) How do I create a column that will default to the current time?
+ 4.21) How do I create a column that will default to the current time?
Use now():
CREATE TABLE test (x int, modtime timestamp DEFAULT now() );
- 4.23) Why are my subqueries using IN so slow?
+ 4.22) Why are my subqueries using IN so slow?
Currently, we join subqueries to outer queries by sequentially
scanning the result of the subquery for each row of the outer query. A
We hope to fix this limitation in a future release.
- 4.24) How do I perform an outer join?
+ 4.23) How do I perform an outer join?
PostgreSQL 7.1 and later supports outer joins using the SQL standard
syntax. Here are two examples:
The problem could be a number of things. Try testing your user-defined
function in a stand-alone test program first.
- 5.2) What does the message "NOTICE:PortalHeapMemoryFree: 0x402251d0 not in
- alloc set!" mean?
-
- You are pfree'ing something that was not palloc'ed. Beware of mixing
- malloc/free and palloc/pfree.
-
- 5.3) How can I contribute some nifty new types and functions to PostgreSQL?
+ 5.2) How can I contribute some nifty new types and functions to PostgreSQL?
Send your extensions to the pgsql-hackers mailing list, and they will
eventually end up in the contrib/ subdirectory.
- 5.4) How do I write a C function to return a tuple?
+ 5.3) How do I write a C function to return a tuple?
This requires wizardry so extreme that the authors have never tried
it, though in principle it can be done.
- 5.5) I have changed a source file. Why does the recompile not see the
+ 5.4) I have changed a source file. Why does the recompile not see the
change?
The Makefiles do not have the proper dependencies for include files.
projects / postgresql.git / commitdiff