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PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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Repeat each row of data.frame the number of times specified in a column
...ndRows(df, "freq")
Simple syntax, very fast, works on data.frame or data.table.
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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org.hibernate.MappingException: Could not determine type for: java.util.List, at table: College, for
I'm using Hibernate for all CRUD operations in my project. It doesn't work for One-To-Many and Many-To-One relationships. It gives me the below error.
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Regular expression for a string that does not start with a sequence
I'm processing a bunch of tables using this program , but I need to ignore ones that start with the label "tbd_". So far I have something like [^tbd_] but that simply not match those characters.
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Rails: Adding an index after adding column
Suppose I created a table table in a Rails app. Some time later, I add a column running:
5 Answers
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Pros and Cons of Interface constants [closed]
...a great solid design. But there are times when good enough really is acceptable (and it takes an experienced developer to understand the difference), and in those cases it's fine.
Again, that's just my view on it...
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Find all storage devices attached to a Linux machine [closed]
I have a need to find all of the writable storage devices attached to a given machine, whether or not they are mounted.
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How does one reorder columns in a data frame?
...ec]
return(data)
}
Now the OP's request becomes as simple as this:
table <- data.frame(Time=c(1,2), In=c(2,3), Out=c(3,4), Files=c(4,5))
table
## Time In Out Files
##1 1 2 3 4
##2 2 3 4 5
arrange.vars(table, c("Out"=2))
## Time Out In Files
##1 1 3 2 4
##2...
App Inventor Tutorials and Examples: Dynamic Table Layout | Pura Vida Apps
...vacy Policy Contact Dynamic Table Layout and Table Listpicker Thank you Christopher for being the sponsor of the App Inventor 2 version! It was asked in the App Inventor Forum, how to display a table in App Inventor without knowing how m...
What is the argument for printf that formats a long?
...y really really knew what they were doing editing a piece of x-platform portable code. Even then, they probably would have used a macro instead to capture the semantic meaning of the type (eg uint64_t).
char c; // 8 bits
short s; // 16 bits
int i; // 32 bits (on modern platforms)...