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Reference - What does this error mean in PHP?
...m. (Note: You might have multiple blocks if you had code that was automatically constructed)
Also make sure you don't have any Byte Order Marks in your code, for example when the encoding of the script is UTF-8 with BOM.
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Headers already sent by PHP
All PHP "Headers already sen...
Are there legitimate uses for JavaScript's “with” statement?
...ous as to how I might make effective use of with , while avoiding its pitfalls.
31 Answers
...
How to think in data stores instead of databases?
...
The datastore makes no distinction between inserts and updates. When you call put() on an entity, that entity gets stored to the datastore with its unique key, and anything that has that key gets overwritten. Basically, each entity kind in the datastore acts like an enormous map or sorted list.
Que...
Is there a MySQL option/feature to track history of changes to records?
...ant to audit the changes to the data - who did what and when?", you can usually use audit tables (as per the trigger example Keethanjan posted). I'm not a huge fan of triggers, but it has the great benefit of being relatively painless to implement - your existing code doesn't need to know about the ...
VIM Disable Automatic Newline At End Of File
So I work in a PHP shop, and we all use different editors, and we all have to work on windows. I use vim, and everyone in the shop keeps complaining that whenever I edit a file there is a newline at the bottom. I've searched around and found that this is a documented behavior of vi & vim... but I w...
Quick easy way to migrate SQLite3 to MySQL? [closed]
...y's built a solid library that can convert between the two.
Here a list of ALL the differences in SQL syntax that I know about between the two file formats:
The lines starting with:
BEGIN TRANSACTION
COMMIT
sqlite_sequence
CREATE UNIQUE INDEX
are not used in MySQL
SQLite uses CREATE TABLE/INSERT ...
How to plot two columns of a pandas data frame using points?
...
You can specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(...
What does the variable $this mean in PHP?
I see the variable $this in PHP all the time and I have no idea what it's used for. I've never personally used it.
10 An...
C# operator overload for `+=`?
...nguage has its own operators list, which are compiled in a special method calls, and CLR itself doesn't know anything about operators. So let's see what exactly stays behind the + and += operators.
See this simple code:
Decimal d = 10M;
d = d + 10M;
Console.WriteLine(d);
Let view the IL-code for...
Reference — What does this symbol mean in PHP?
... have the same results.
Pre-increment is a little bit faster because it really increments the variable and after that 'returns' the result. Post-increment creates a special variable, copies there the value of the first variable and only after the first variable is used, replaces its value with seco...