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Combine two data frames by rows (rbind) when they have different sets of columns
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An alternative with data.table:
library(data.table)
df1 = data.frame(a = c(1:5), b = c(6:10))
df2 = data.frame(a = c(11:15), b = c(16:20), c = LETTERS[1:5])
rbindlist(list(df1, df2), fill = TRUE)
rbind will also work in data.table as long as the...
Location of my.cnf file on macOS
...te: On Unix platforms, MySQL ignores configuration files that are world-writable. This is intentional as a security measure.
Additionally on Mac there is a simple way to check it.
Run: sudo fs_usage | grep my.cnf
This will report any filesystem activity in real-time related to that file.
In a...
MongoDB, remove object from array
...id" : 3
}
]
}
MY QUERY:->
db.getCollection('play_table').update({},{$pull:{"data":{"id":3}}},{multi:true}
OutPut:->
{
"_id" : ObjectId("5806056dce046557874d3ab18"),
"data" : [
{
"id" : 1
},
{
"id" ...
Keeping it simple and how to do multiple CTE in a query
I have this simple T-SQL query, it emits a bunch of columns from a table and also joins information from other related tables.
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Center image in div horizontally [duplicate]
...x solid #888;
width: 100px;
height: 100px;
}
.inner
{
display:table-cell;
height: 100px;
width: 100px;
vertical-align: middle;
}
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Rails 3 execute custom sql query without a model
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Maybe try this:
ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)
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How to calculate moving average using NumPy?
...inciple behind this answer is widely used in image processing (summed area tables they call it), so the issue had to be in the implementation. A good example of being bit by premature optimization, since I kind of recall doing the operation in-place "because it will be more efficient." On the bright...
How to escape a pipe char in a code statement in a markdown table?
On GitHub I want to build a table containing pieces of code in Markdown. It works fine except when I put a pipe char (i.e. | ) between the backtick (i.e. ` ) chars.
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NoSql Crash Course/Tutorial [closed]
...I'm really stuck in a relational-db mindset thinking of things in terms of tables and joins...
9 Answers
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Using Position Relative/Absolute within a TD?
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This is because according to CSS 2.1, the effect of position: relative on table elements is undefined. Illustrative of this, position: relative has the desired effect on Chrome 13, but not on Firefox 4. Your solution here is to add a div around your content and put the position: relative on that di...