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Best way to select random rows PostgreSQL
...ll:
SELECT * FROM f_random_sample();
SELECT * FROM f_random_sample(500, 1.05);
You could even make this generic to work for any table: Take the name of the PK column and the table as polymorphic type and use EXECUTE ... But that's beyond the scope of this question. See:
Refactor a PL/pgSQL func...
Practical usage of setjmp and longjmp in C
...can be used practically in embedded programming? I know that these are for error handling. But I'd like to know some use cases.
...
Check if database exists in PostgreSQL using shell
...ou try to create a database that already exists, postgresql will return an error message like this:
postgres@desktop:~$ createdb template1
createdb: database creation failed: ERROR: database "template1" already exists
sha...
How can I generate a self-signed certificate with SubjectAltName using OpenSSL? [closed]
... = @alternate_names under v3_ca section. Could it be a typo? Here's the error I get: error:22097069:X509 V3 routines:DO_EXT_NCONF:invalid extension string:v3_conf.c:139:name=subjectAltName,section=@alternate_names 140487468840608:error:22098080:X509 V3 routines:X509V3_EXT_nconf:error in extension...
An example of how to use getopts in bash
...f expected arguments,
h - check for option -h without parameters; gives error on unsupported options;
h: - check for option -h with parameter; gives errors on unsupported options;
abc - check for options -a, -b, -c; gives errors on unsupported options;
:abc - check for options -a, -b, -c; silence...
How do I trim leading/trailing whitespace in a standard way?
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– Adam Rosenfield
Mar 16 '10 at 15:05
15
@nvl: No. str is a local variable, and changing it doe...
Python Dictionary Comprehension
...y:'your value here' for key in old_dict.keys()}
You're receiving a SyntaxError because when you write
d = {}
d[i for i in range(1, 11)] = True
you're basically saying: "Set my key 'i for i in range(1, 11)' to True" and "i for i in range(1, 11)" is not a valid key, it's just a syntax err...
Received fatal alert: handshake_failure through SSLHandshakeException
...but without any luck, because I have as a result from server the following error:
19 Answers
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psql: FATAL: database “” does not exist
...
In my case i wrote $ createdb -h localhost to solve the error could not connect to database postgres: could not connect to server. After that i may connect to postgresql console via psql -h localhost.
– ExiRe
Jan 9 '14 at 14:23
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How can I profile Python code line-by-line?
...ads 0 demo/threads.py
Command line: ['demo/threads.py']
Total duration: 1.00573s
File: demo/threads.py
File duration: 1.00168s (99.60%)
Line #| Hits| Time| Time per hit| %|Source code
------+----------+-------------+-------------+-------+-----------
1| 2| 3.21865e-05|...