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How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
What differences, if any, between C++03 and C++11 can be detected at run-time?
...onstrate breaking changes. The following is a tweaked testcase, which initially was used to demonstrate such a change, but now is used to test for C++0x or C++03.
struct X { };
struct Y { X x1, x2; };
struct A { static X B(int); };
typedef A B;
struct C : A {
using ::B::B; // (inheriting const...
Cannot run Eclipse; JVM terminated. Exit code=13
...
Okey, I solve it. I just reinstall JDK 64-bit, re-extact eclipse-64bit and edit eclipse.ini again.
– Prince OfThief
Feb 9 '11 at 14:13
...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用 - c++1...
1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@4，该符号在函数 _main 中被引用
1>NetClient.obj : error LNK2019: 无法解析的外部符号 _inet_ntoa@4，该符号在函数 _main 中被引用
1>NetClient.obj : error LNK2019: 无法解析的外部符...
How do I iterate over an NSArray?
...
The generally-preferred code for 10.5+/iOS.
for (id object in array) {
// do something with object
}
This construct is used to enumerate objects in a collection which conforms to the NSFastEnumeration protocol. This approach ha...
How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
... is exported. To export in a vector format, use To PDF File, instead. This allows for simplified editing using Inkscape (or other vector image editor).
These instructions may work for SQL Developer 3.2.09.23 to 4.1.3.20.
sh...
How to get a random number in Ruby
...6). A roll in craps could be simulated with 2 + rand(6) + rand(6).
Finally, if you just need a random float, just call rand with no arguments.
As Marc-André Lafortune mentions in his answer below (go upvote it), Ruby 1.9.2 has its own Random class (that Marc-André himself helped to debug,...
How to write a multidimensional array to a text file?
...is specified by the comments kwarg). (This looks more verbose than it actually is...)
import numpy as np
# Generate some test data
data = np.arange(200).reshape((4,5,10))
# Write the array to disk
with open('test.txt', 'w') as outfile:
# I'm writing a header here just for the sake of readabil...
importing pyspark in python shell
...on to $PYTHONPATH.
– kingledion
Oct 10 '19 at 16:10
Another point is spark-submit is a shell script, which helps you c...
How to set HttpResponse timeout for Android in Java
...oment once my HTTP request is made, I then check the status code upon the call returning, however I get a NullPointerException when checking this code if the call has timed out... basically, how do I handle the situation when the call does timeout? (I'm using very similar code to your answer given)
...