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MySQL Query to select data from last week?
Hi I have a table with a date field and some other information.
I want to select all entries from the past week, (week start from Sunday).
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How to save a data.frame in R?
...ta.Rda")
Then load it with:
load("data.Rda")
You could also use write.table() or something like that to save the table in plain text, or dput() to obtain R code to reproduce the table.
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How to change column datatype from character to numeric in PostgreSQL 8.4
...rom old to new type.
So this might work (depending on your data):
alter table presales alter column code type numeric(10,0) using code::numeric;
-- Or if you prefer standard casting...
alter table presales alter column code type numeric(10,0) using cast(code as numeric);
This will fail if you h...
MySQL Insert Where query
...TO Users(weight, desiredWeight)
SELECT weight, desiredWeight
FROM AnotherTable
WHERE id = 1
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Is there an auto increment in sqlite?
I am trying to create a table with an auto-incrementing primary key in Sqlite3 . I am not sure if this is really possible, but I am hoping to only have to designate the other fields.
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How can I view live MySQL queries?
...ry query run results in the query being inserted into some sort of history table, and then create a separate page to access this information.
Do be aware that this will probably considerably slow down everything on the server though, with adding an extra INSERT on top of every single query.
Edit...
UITableView didSelectRowAtIndexPath: not being called on first tap
I'm having an issue with UITableView's didSelectRowAtIndexPath .
16 Answers
16
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Remove an entire column from a data.frame in R
... long amount of time and/or fail due to out of memory errors. Package data.table helps address this problem with the := operator:
library(data.table)
> dt <- data.table(a = 1, b = 1, c = 1)
> dt[,a:=NULL]
b c
[1,] 1 1
I should put together a bigger example to show the differences. I...
Quick Way to Implement Dictionary in C
...ection 6.6 of The C Programming Language presents a simple dictionary (hashtable) data structure. I don't think a useful dictionary implementation could get any simpler than this. For your convenience, I reproduce the code here.
struct nlist { /* table entry: */
struct nlist *next; /* next ent...
How to set data attributes in HTML elements
...bjValues['field.dataset.customval'] = field.dataset.customval
console.table([objValues])
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<h1>Example</h1>
<form>
<input id="textfield" type="text" data-customval=...