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Postgres: INSERT if does not exist already
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Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON CONFLICT DO NOTHING/UPDATE
It solves many of the subtle problems you can run into when using concurrent operation, which some other answers propose.
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Where can I find the IIS logs?
... exactly as explained in their install guide, but am having some problems, and would like to see what the IIS log has to say. Embarrassingly enough, the problem is I can't find the log files!
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Programmatically Lighten or Darken a hex color (or rgb, and blend colors)
...tically lighten or darken a hex color by a specific amount. Just pass in a string like "3F6D2A" for the color ( col ) and a base10 integer ( amt ) for the amount to lighten or darken. To darken, pass in a negative number (i.e. -20 ).
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How do I trap ctrl-c (SIGINT) in a C# console app
...ss event is used for this. This is how it's used:
public static void Main(string[] args)
{
Console.CancelKeyPress += delegate {
// call methods to clean up
};
while (true) {}
}
When the user presses Ctrl + C the code in the delegate is run and the program exits. This allows y...
How to copy from CSV file to PostgreSQL table with headers in CSV file?
...w which has the column names
for col in execute format ('select unnest(string_to_array(trim(temp_table::text, ''()''), '','')) from temp_table where col_1 = %L', col_first)
loop
execute format ('alter table temp_table rename column col_%s to %s', iter, col);
iter := iter + 1;...
MySQL Data - Best way to implement paging?
...ments, the first argument specifies the offset of the first row to return, and the second specifies the maximum number of rows to return. The offset of the initial row is 0 (not 1):
SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15
To retrieve all rows from a certain offset up to the end of the r...
How to solve javax.net.ssl.SSLHandshakeException Error?
...public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType)
{
//No need to implement.
}
public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType)
{
//No n...
Set selected option of select box
... edited May 16 '15 at 1:56
andrewtweber
19.4k1919 gold badges7575 silver badges103103 bronze badges
answered Jan 13 '11 at 12:48
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What does 'synchronized' mean?
...ns, so consider this code
public class SOP {
public static void print(String s) {
System.out.println(s+"\n");
}
}
public class TestThread extends Thread {
String name;
TheDemo theDemo;
public TestThread(String name,TheDemo theDemo) {
this.theDemo = theDemo;
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JavaScript - Get minutes between two dates
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Old answer, but you should never use new Date(string) with a format other than an ISO-8601 format string. See Why does Date.parse give incorrect results?, or just use numbers (e.g., new Date(2011, 9, 9, 12, 0, 0); just remember months are 0 based).
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