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When should I use mmap for file access?
...om. (The OS can detect which pages are unmodified by initially marking writable mmap'd pages as read only and catching seg faults, similar to Copy on Write strategy).
mmap is also useful for inter process communication. You can mmap a file as read / write in the processes that need to communica...
django syncdb and an updated model
...ngo currently does not do this automatically. Your options are:
Drop the table from the database, then recreate it in new form using syncdb.
Print out SQL for the database using python manage.py sql (appname), find the added line for the field and add it manually using alter table SQL command. (Th...
Specify custom Date format for colClasses argument in read.table/read.csv
... way to specify the Date format when using the colClasses argument in read.table/read.csv?
4 Answers
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The Role Manager feature has not been enabled
...thod will run just fine (if you haven't messed elsewhere) and create a few tables in your Database;
Press Ctrl+W+L to open the Server Explorer and you should be able to check in Data Connections > DefaultConnection > Tables the Roles and UsersInRoles tables among the newly created tables!
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Can we have multiple in same ?
Can we have multiple <tbody> tags in same <table> ? If yes then in what scenarios should we use multiple <tbody> tags?
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How should I choose an authentication library for CodeIgniter? [closed]
... set
Very good documentation
Simple and elegant database design (just 4 DB tables)
Most features are optional and easily configured
Language file support
reCAPTCHA supported
Hooks into CI's validation system
Activation emails
Login with email, username or both (configurable)
Unactivated accounts aut...
How to do an INNER JOIN on multiple columns
...nds flights either by the city name or the airport code, but the flights table only contains the airport codes so if I want to search by city I have to join on the airports table.
...
Static Vs. Dynamic Binding in Java
...e OverridingInternalExample, we can see that compiler generates a constant table where it assigns integer codes to every method call and byte code for the program which I have extracted and included in the program itself (see the comments below every method call)
By looking at above code we can s...
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...
What is the recommended batch size for SqlBulkCopy?
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One thing to consider is if the table is empty and has indexes. In those cases you might want to upload everything in one batch as mentioned here: technet.microsoft.com/en-us/library/ms177445(v=sql.105).aspx "If you bulk import data into an empty table with...