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Is there a good reason to use upper case for SQL keywords? [closed]
...lies on the reader's ability to distinguish keywords versus identifiers in order to mentally parse the syntax.
The direct answer to your question, then, is more an answer to “why does the reader of SQL code benefit so much from uppercase keywords, when that's not as true for most modern languages...
Convert HTML + CSS to PDF [closed]
...he solution seems to be HTML2PDF. DOMPDF did a terrible job with tables, borders and even moderately complex layout and htmldoc seems reasonably robust but is almost completely CSS-ignorant and I don't want to go back to doing HTML layout without CSS just for that program.
HTML2PDF looked the most...
Java regex capturing groups indexes
...group in the pattern start indexing from 1. The indices are defined by the order of the opening parentheses of the capturing groups. As an example, here are all 5 capturing groups in the below pattern:
(group)(?:non-capturing-group)(g(?:ro|u)p( (nested)inside)(another)group)(?=assertion)
| | ...
Predicate in Java
...es.filter
Returns the elements that satisfy a predicate.
On higher-order function
Predicate allows Iterables.filter to serve as what is called a higher-order function. On its own, this offers many advantages. Take the List<Integer> numbers example above. Suppose we want to test if all...
How to store arrays in MySQL?
...the key.". An array does too much. It has multiple facts and it stores the order (which is not related to the relation itself). And the performance is poor (see above).
Imagine that you have a person table and you have a table with phone calls by people. Now you could make each person row have a li...
Is there any reason to use a synchronous XMLHttpRequest?
... This suits the majority of development needs where the desire is to have ordered, non-blocking events that enable the browsers to retain responsiveness for the user (good UX).
As stated in the Mozilla docs there are cases where you have to use synchronous requests; however, also listed is a workar...
SQL query to group by day
...ADD SaleDay AS DAY(Created) PERSISTED
and now you could easily group by, order by etc. by day, month or year of the sale:
SELECT SaleDay, SUM(Amount)
FROM dbo.Sales
GROUP BY SaleDay
Those calculated fields will always be kept up to date (when your "Created" date changes), they're part of your t...
How to access array elements in a Django template?
... # method call
foo[bar] # list-index lookup
It tries them in this order until it finds a match. So foo.3 will get you your list index because your object isn't a dict with 3 as a key, doesn't have an attribute named 3, and doesn't have a method named 3.
...
Why is using “for…in” for array iteration a bad idea?
...er inherited properties, a thing that sometimes is not desired.
Also, the order of iteration is not guaranteed by the spec., meaning that if you want to "iterate" an array object, with this statement you cannot be sure that the properties (array indexes) will be visited in the numeric order.
For e...
When to use PNG or JPG in iPhone development?
... decoding the image. You may need to decrease the quality of your JPG's in order to see a real benefit in file size but then you are displaying non-optimal images.
File size is certainly a factor but there are other considerations at play as well when choosing an image format.
...