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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...use a query like this: "start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * ...
How to change the output color of echo in Linux
...put accepts scripts containing one command per line, which are executed in order before tput exits.
Avoid temporary files by echoing a multiline string and piping it:
echo -e "setf 7\nsetb 1" | tput -S # set fg white and bg red
See also
See man 1 tput
See man 5 terminfo for the complete lis...
LLVM vs clang on OS X
...ediate representation on its own; it needs a language-specific frontend in order to do so. If people just refer to LLVM, they probably mean just the low-level library and tools. Some people might refer to Clang or llvm-gcc incorrectly as "LLVM", which may cause some confusion.
llvm-gcc is a modifie...
Unable to locate tools.jar
...
Add JAVA_HOME and the /bin directory to your path. You realize that this answer is two years old, right?
– duffymo
Jul 23 '13 at 12:52
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Handling an empty UITableView. Print a friendly message
...xtension:
import UIKit
extension UITableView {
func setEmptyMessage(_ message: String) {
let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.bounds.size.width, height: self.bounds.size.height))
messageLabel.text = message
messageLabel.textColor = .black
...
When would you use a List instead of a Dictionary?
...
The List would also be useful when you care about the order of the items.
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How to stop unwanted UIButton animation on title change?
...
This works for custom buttons:
[UIView setAnimationsEnabled:NO];
[_button setTitle:@"title" forState:UIControlStateNormal];
[UIView setAnimationsEnabled:YES];
For system buttons you need to add this before re-enabling animations (thank you @Klaas):
[_button layoutIfNeeded];
...
Naming returned columns in Pandas aggregate function? [duplicate]
...l() function on the multi-level column to form new labels:
df.columns = ["_".join(x) for x in df.columns.ravel()]
For example:
import pandas as pd
import pandas.rpy.common as com
import numpy as np
data = com.load_data('Loblolly')
print(data.head())
# height age Seed
# 1 4.51 3 3...
How to add a button dynamically in Android?
...d(R.id.buttonlayout);
LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
ll.addView(myButton, lp);
Have a look to this example
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Why would finding a type's initializer throw a NullReferenceException?
....cs:
(196c.1874): Access violation - code c0000005 (first chance)
mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3:
000007fe`e5735403 488b4608 ...