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Error Code: 1005. Can't create table '…' (errno: 150)
...ey name to test for this.
One or both of your tables is a MyISAM table. In order to use foreign keys, the tables must both be InnoDB. (Actually, if both tables are MyISAM then you won’t get an error message - it just won’t create the key.) In Query Browser, you can specify the table type.
You ha...
Can a variable number of arguments be passed to a function?
...
# 1
# 2
# 3
# banan = 123
They must be both declared and called in that order, that is the function signature needs to be *args, **kwargs, and called in that order.
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NHibernate ISession Flush: Where and when to use it, and why?
...it()
from ISession.Flush()
The SQL statements are issued in the following order
all entity insertions, in the same order the corresponding objects were saved using ISession.Save()
all entity updates
all collection deletions
all collection element deletions, updates and insertions
all collection in...
Sort Dictionary by keys
...
If you want to iterate over both the keys and the values in a key sorted order, this form is quite succinct
let d = [
"A" : [1, 2],
"Z" : [3, 4],
"D" : [5, 6]
]
Swift 1,2:
for (k,v) in Array(d).sorted({$0.0 < $1.0}) {
println("\(k):\(v)")
}
Swift 3+:
for (k,v) in Array(d).sort...
Ruby: Can I write multi-line string with no concatenation?
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p <<END_SQL.gsub(/\s+/, " ").strip
SELECT * FROM users
ORDER BY users.id DESC
END_SQL
# >> "SELECT * FROM users ORDER BY users.id DESC"
The latter would mostly be for situations that required more flexibility in the processing. I personally don't like it, it puts the proc...
Split a vector into chunks in R
... f)
if(force.number.of.groups) {
g.names <- names(g)
g.names.ordered <- as.character(sort(as.numeric(g.names)))
} else {
g.names <- names(g[-length(g)])
g.names.ordered <- as.character(sort(as.numeric(g.names)))
g.names.ordered <- c(g.names.ordered, "overflow"...
What is a “Bitmap heap scan” in a query plan?
... is different from an index scan, where the index is visited row by row in order -- meaning a disk page may get visited multiple times.
Re: the question in your comment... Yep, that's exactly it.
An index scan will go through rows one by one, opening disk pages again and again, as many times as ...
How do I tell Matplotlib to create a second (new) plot, then later plot on the old one?
...ruggling is creating a function which gets data_plot matrix, file name and order as parameter to create boxplots from the given data in the ordered figure (different orders = different figures) and save it under the given file_name.
def plotFigure(data_plot,file_name,order):
fig = plt.figure(or...
what is the basic difference between stack and queue?
...
You can think of both as an ordered list of things (ordered by the time at which they were added to the list). The main difference between the two is how new elements enter the list and old elements leave the list.
For a stack, if I have a list a, b, c...
Are 2^n and n*2^n in the same time complexity?
...
You will have to go to the formal definition of the big O (O) in order to answer this question.
The definition is that f(x) belongs to O(g(x)) if and only if the limit limsupx → ∞ (f(x)/g(x)) exists i.e. is not infinity. In short this means that there exists a constant M, such that v...