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Algorithm to find top 10 search terms
...ue ID for each. This whole set of data can be loaded into memory as a hash table, consuming roughly 300MB memory. (We have implemented our own hash table. The Java's implementation takes huge memory overhead)
Each phrase then can be identified as an array of integers.
This is important, because s...
How to calculate percentage with a SQL statement
I have a SQL Server table that contains users & their grades. For simplicity's sake, lets just say there are 2 columns - name & grade . So a typical row would be Name: "John Doe", Grade:"A".
...
Difference between Divide and Conquer Algo and Dynamic Programming
...blem is solved only once and the result of each sub-problem is stored in a table ( generally implemented as an array or a hash table) for future references. These sub-solutions may be used to obtain the original solution and the technique of storing the sub-problem solutions is known as memoization....
What is the difference between Scope_Identity(), Identity(), @@Identity, and Ident_Current()?
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The ident_current(name) returns the last identity created for a specific table or view in any session.
The identity() function is not used to get an identity, it's used to create an identity in a select...into query.
The session is the database connection. The scope is the current query or the c...
How do I use LINQ Contains(string[]) instead of Contains(string)
...ids = arrayofuids.Select(id => int.Parse(id)).ToList();
var selected = table.Where(t => uids.Contains(t.uid));
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Request is not available in this context
...ot leave the fields null. (In my case, don't write a record to one logging table, but it would help if there were a good way to determine whether or not is available.)
– Zarepheth
Sep 11 '14 at 21:47
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SCOPE_IDENTITY() for GUIDs?
...ng OUTPUT. This works when you're inserting multiple records also.
CREATE TABLE dbo.GuidPk (
ColGuid uniqueidentifier NOT NULL DEFAULT NewSequentialID(),
Col2 int NOT NULL
)
GO
DECLARE @op TABLE (
ColGuid uniqueidentifier
)
INSERT INTO dbo.GuidPk (
Col2
)
OUTPUT in...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...ow_add=True in the constructor, the datetime referenced by my_date is "immutable" (only set once when the row is inserted to the table).
With auto_now=True, however, the datetime value will be updated every time the object is saved.
This was definitely a gotcha for me at one point. For reference, ...
update columns values with column of another table based on condition [duplicate]
I have two tables...
2 Answers
2
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Create an empty data.frame
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You could use read.table with an empty string for the input text as follows:
colClasses = c("Date", "character", "character")
col.names = c("Date", "File", "User")
df <- read.table(text = "",
colClasses = colClasses,
...