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Simple basic explanation of a Distributed Hash Table (DHT)
...tore a particular key is found by hashing that key, so in effect your hash-table buckets are now independent nodes in a network.
This gives a lot of fault-tolerance and reliability, and possibly some performance benefit, but it also throws up a lot of headaches. For example, what happens when a nod...
update columns values with column of another table based on condition [duplicate]
I have two tables...
2 Answers
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Can a class member function template be virtual?
...teresting techniques stemming from combining polymorphism and templates, notably so-called type erasure.
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How to import multiple .csv files at once?
...r answers using things like do.call(rbind,...), dplyr::bind_rows() or data.table::rbindlist().
If you really want each data frame in a separate object, even though that's often inadvisable, you could do the following with assign:
temp = list.files(pattern="*.csv")
for (i in 1:length(temp)) assign(...
SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER j...
How do I get list of all tables in a database using TSQL?
What is the best way to get the names of all of the tables in a specific database on SQL Server?
17 Answers
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Good way to use table alias in Update statement?
I'm using SQL Server, and trying to update rows from within the same table. I want to use a table alias for readability.
2 ...
Adding gif image in an ImageView in android
...eight; // full image height
protected boolean gctFlag; // global color table used
protected int gctSize; // size of global color table
protected int loopCount = 1; // iterations; 0 = repeat forever
protected int[] gct; // global color table
protected int[] lct; // local color tab...
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In 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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How to add a WiX custom action that happens only on uninstall (via MSI)?
...ly on uninstalls - not upgrades, not repairs or modifies. According to the table above I had to use
<Custom Action='CA_ID' Before='other_CA_ID'>
(NOT UPGRADINGPRODUCTCODE) AND (REMOVE="ALL")</Custom>
And it worked!
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