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Difference between VARCHAR and TEXT in MySQL [duplicate]
...imit for your table
Reasons to use VARCHAR:
If you want to store a few words or a sentence
If you want to index the (entire) column
If you want to use the column with foreign-key constraints
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Get record counts for all tables in MySQL database
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Ooops... wish I would have seen the word "Estimated" before hand... like yesterday! Shouldn't answer be rejected? As OP did not ask for "estimated" and it seems silly to think that he may want an estimate. "estimate"Could save maroons like me from missing the "...
How do you allow spaces to be entered using scanf?
...ehavior if numeric conversion overflows (N1570 7.21.6.2p10, last sentence, wording unchanged since C89) which means none of the scanf functions can safely be used for numeric conversion of untrusted input.
– zwol
Apr 30 '19 at 18:07
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How to disable and re-enable console logging in Python?
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CRITICAL was the word I was looking for. Thanks.
– Nishant
Apr 29 '19 at 12:59
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INSERT IF NOT EXISTS ELSE UPDATE?
...lidDate>phonebook2.validDate;
Be warned that at this point the actual word "UPSERT" is not part of the upsert syntax.
The correct syntax is
INSERT INTO ... ON CONFLICT(...) DO UPDATE SET...
and if you are doing INSERT INTO SELECT ... your select needs at least WHERE true to solve parser ambi...
What is a columnar database?
...se is a concept rather a particular architecture/implementation. In other words, there isn't one particular description on how these databases work; indeed, several are build upon traditional, row-oriented, DBMS, simply storing the info in tables with one (or rather often two) columns (and adding t...
What's the difference between RANK() and DENSE_RANK() functions in oracle?
... 8 | 8 | 5 |
+---+------------+------+------------+
In words
ROW_NUMBER() attributes a unique value to each row
RANK() attributes the same row number to the same value, leaving "holes"
DENSE_RANK() attributes the same row number to the same value, leaving no "holes"
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Random record in ActiveRecord
...can (or table scan, in case clustered index is used like InnoDB). In other words, it's O(N) operation but "WHERE id >= #{rand_id} ORDER BY id ASC LIMIT 1" is O(log N), which is much faster.
– kenn
May 6 '11 at 1:02
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Why do python lists have pop() but not push()
...rticular
semantics, write a little class that
uses a lists
In other words, for stacks implemented directly as Python lists, which already supports fast append(), and del list[-1], it makes sense that list.pop() work by default on the last element. Even if other languages do it differently.
I...
Is there a way to change the environment variables of another process in Unix?
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@kilaka: The key word is the second one — No. The rest of the answer is saying that if you have root privileges or are running a debugger, then maybe you can do it, but for all practical purposes, the answer is No.
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