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When to use an interface instead of an abstract class and vice versa?
...ric OOP question. I wanted to do a generic comparison between an interface and an abstract class on the basis of their usage.
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
... I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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retrieve links from web page using python and BeautifulSoup [closed]
How can I retrieve the links of a webpage and copy the url address of the links using Python?
16 Answers
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How to use OpenSSL to encrypt/decrypt files?
I want to crypt and decrypt one file using one password.
10 Answers
10
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How to send objects through bundle
...of three things:
1) You can break the object down to its constitute data, and if what's on the other end has knowledge of the same sort of object, it can assemble a clone from the serialized data. That's how most of the common types pass through bundles.
2) You can pass an opaque handle. If you ...
Should I use the datetime or timestamp data type in MySQL?
Would you recommend using a datetime or a timestamp field, and why (using MySQL)?
39 Answers
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What is array to pointer decay?
...mbers = 0x5a5aff23. More importantly the term decay signifies loss of type and dimension; numbers decay into int* by losing the dimension information (count 5) and the type is not int [5] any more. Look here for cases where the decay doesn't happen.
If you're passing an array by value, what you're ...
ORA-30926: unable to get a stable set of rows in the source tables
...cified in USING clause. This probably means that TABLE_A is a parent table and the same ROWID is returned several times.
You could quickly solve the problem by using a DISTINCT in your query (in fact, if 'Y' is a constant value you don't even need to put it in the query).
Assuming your query is co...
What is the difference between LL and LR parsing?
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At a high level, the difference between LL parsing and LR parsing is that LL parsers begin at the start symbol and try to apply productions to arrive at the target string, whereas LR parsers begin at the target string and try to arrive back at the start symbol.
An LL parse i...
Can someone explain the right way to use SBT?
I'm getting out off the closet on this! I don't understand SBT. There, I said it, now help me please.
4 Answers
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