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How to convert TimeStamp to Date in Java?
... .atStartOfDay( ZoneId.of( "Africa/Tunis" ) )
.toEpochSecond()
…
"SELECT * FROM orders WHERE placed >= ? AND placed < ? ; "
…
myPreparedStatement.setObject( 1 , start )
myPreparedStatement.setObject( 2 , stop )
java.time
You are using troublesome old date-time classes that are...
Returning IEnumerable vs. IQueryable
...mers = custs.Where(c => c.IsGold);
That code will execute SQL to only select gold customers. The following code, on the other hand, will execute the original query in the database, then filtering out the non-gold customers in the memory:
IEnumerable<Customer> custs = ...;
// Later on...
...
mysql - how many columns is too many?
...every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name the columns you need.
As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entit...
How to see log files in MySQL?
...print the value of error log, run this command in the terminal:
mysql -e "SELECT @@GLOBAL.log_error"
To read content of the error log file in real time, run:
sudo tail -f $(mysql -Nse "SELECT @@GLOBAL.log_error")
Note: Hit Control-C when finish
When general log is enabled, try:
sudo tail -f ...
Python how to write to a binary file?
...ry vs. text mode means in 2.x. It doesn't matter what type your bytes come from. (In 3.x, of course, binary vs. text mode means that you write bytes vs. unicode, and the \r\n feature is part of the universal newlines options for text.)
– abarnert
Dec 13 '14 at ...
Java switch statement: Constant expression required, but it IS constant
...ice.Choice1;
switch(ch) {
case Choice1:
System.out.println("Choice1 selected");
break;
case Choice2:
System.out.println("Choice2 selected");
break;
case Choice3:
System.out.println("Choice3 selected");
break;
}
}
}
Source:
Switch statement with enum
...
:first-child not working as expected
I'm trying to select the first h1 inside a div with a class called detail_container . It works if h1 is the first element within this div , but if it comes after this ul it won't work.
...
What is a semaphore?
...ey will be sufficient to protect that resource and prevent multiple people from using it simultaneously.
If there are multiple bathrooms, one might be tempted to key them alike and make multiple keys - this is similar to a semaphore being mis-used. Once you have a key you don't actually know which ...
Entity Framework: There is already an open DataReader associated with this Command
...al commands executed on single connection (or single command with multiple selects) while next DataReader is executed before first one has completed the reading. The only way to avoid the exception is to allow multiple nested DataReaders = turn on MultipleActiveResultSets. Another scenario when this...
How to deal with SettingWithCopyWarning in Pandas?
...owing, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] =...