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Tactics for using PHP in a high-load site
...lize your schemas. This means that rather than to have multiple relational tables, you should instead opt to have one big table. In general, joins are a waste of precious DB resources because doing multiple prepares and collation burns disk I/O's. Avoid them when you can.
The trade-off here is ...
The difference between fork(), vfork(), exec() and clone()
...s big. I presume this is because the kernel still has to copy all the page tables.
– Martina Ferrari
Mar 15 '16 at 3:04
4
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What are the pros and cons to keeping SQL in Stored Procs versus Code [closed]
... the SQL inline in C# and calling to the SQL Server DB. So I'm trying to establish which, for this particular project, would be best.
...
How do I import .sql files into SQLite 3?
...o, your SQL is invalid - you need ; on the end of your statements:
create table server(name varchar(50),ipaddress varchar(15),id init);
create table client(name varchar(50),ipaddress varchar(15),id init);
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#1071 - Specified key was too long; max key length is 767 bytes
...
767 bytes is the stated prefix limitation for InnoDB tables in MySQL version 5.6 (and prior versions). It's 1,000 bytes long for MyISAM tables. In MySQL version 5.7 and upwards this limit has been increased to 3072 bytes.
You also have to be aware that if you set an index on a...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
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Using the data.table package, which is fast (useful for larger datasets)
https://github.com/Rdatatable/data.table/wiki
library(data.table)
df2 <- setDT(df1)[, lapply(.SD, sum), by=.(year, month), .SDcols=c("x1","x2")]
setDF(df2) # con...
How to print a groupby object
...ibe():
grp = df.groupby['colName']
grp.describe()
This gives you a neat table.
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python pandas remove duplicate columns
...d, the problem is probably with the duplicate column titles.
For a sample table file 'dummy.csv' I made up:
Time H1 N2 Time N2 Time Relative
3 13 13 3 13 0
1 15 15 1 15 14
14 19 19 14 19 14
19 5 5 19 5 1
using read_table gives unique columns and works properly...
Repeater, ListView, DataList, DataGrid, GridView … Which to choose?
...t you trying to achieve
Gridview - Limited in design, works like an html table. More in built functionality like edit/update, page, sort. Lots of overhead.
DataGrid - Old version of the Gridview. A gridview is a super datagrid.
Datalist - more customisable version of the Gridview. Also has some o...
What are the complexity guarantees of the standard containers?
...
I'm not aware of anything like a single table that lets you compare all of them in at one glance (I'm not sure such a table would even be feasible).
Of course the ISO standard document enumerates the complexity requirements in detail, sometimes in various rather r...