Tutorial by Examples: l

From MSDN In a future version of SQL Server, ANSI_NULLS will always be ON and any applications that explicitly set the option to OFF will generate an error. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. ANSI NULLS being set t...

This creates a simple archive of a folder : tar -cf ./my-archive.tar ./my-folder/ Verbose output shows which files and directories are added to the archive, use the -v option: tar -cvf ./my-archive.tar ./my-folder/ For archiving a folder compressed 'gzip', you have to use the -z option : ta...

There is an example for extract a folder from an archive in the current location : tar -xf archive-name.tar If you want to extract a folder from an archive to a specfic destination : tar -xf archive-name.tar -C ./directory/destination

There is an example of listing content : tar -tvf archive.tar The option -t is used for the listing. For listing the content of a tar.gz archive, you have to use the -z option anymore : tar -tzvf archive.tar.gz

Description: Evaluate expression after user's confirmation. Arguments: ng-confirm-click:(expression) Expression to evaluate when confirmed. ng-confirm-message:(template) Message to be shown in confirm dialog. Code: Directives.directive("ngConfirmClick", ["$parse","...

Polymorphism is the ability to perform an action on an object regardless of its type. This is generally implemented by creating a base class and having two or more subclasses that all implement methods with the same signature. Any other function or method that manipulates these objects can call the ...

YAML does not come with a standard PHP installation, instead it needs to be installed as a PECL extension. On linux/unix it can be installed with a simple pecl install yaml Note that libyaml-dev package must be installed on the system, as the PECL package is simply a wrapper around libYAML call...

YAML provides a way to store structured data. The data can be a simple set of name-value pairs or a complex hierarchical data with values even being arrays. Consider the following YAML file: database: driver: mysql host: database.mydomain.com port: 3306 db_name: sample_db ...

General log - all queries - see VARIABLE general_log Slow log - queries slower than long_query_time - slow_query_log_file Binlog - for replication and backup - log_bin_basename Relay log - also for replication general errors - mysqld.err start/stop - mysql.log (not very interesting) - log_err...

How to use conditional execution of command lists Any builtin command, expression, or function, as well as any external command or script can be executed conditionally using the &&(and) and ||(or) operators. For example, this will only print the current directory if the cd command was succ...

First, you need to install django-debug-toolbar: pip install django-debug-toolbar settings.py: Next, include it to project's installed apps, but be careful - it's always a good practice to use a different settings.py file for such development-only apps and middlewares as debug toolbar: # If en...

Lists def lst = ['foo', 'bar', 'baz'] // using implicit argument lst.each { println it } // using explicit argument lst.each { val -> println val } // both print: // foo // bar // baz Iterate with index def lst = ['foo', 'bar', 'baz'] // explicit arguments are required lst.each...

def lst = ['foo', 'bar', 'baz'] lst.collect { it } // ['foo', 'bar', 'baz'] lst.collect { it.toUpperCase() } // ['FOO', 'BAR', 'BAZ'] To collect keys or values from a maps def map = [foo: 'FOO', bar: 'BAR', baz: 'BAZ'] def keys = map.collect { it.key } // ['foo', 'bar', 'baz'] def vals = m...

def lst = [10, 20, 30, 40] lst.findAll { it > 25 } // [30, 40]

def lst = [10, 20, 30, 40] lst.find { it > 25 } // 30. Note: it returns a single value

From lists def lst = ['foo', 'bar', 'baz'] // for each entry return a list containing [key, value] lst.collectEntries { [it, it.toUpperCase()] } // [foo: FOO, bar: BAR, baz: BAZ] // another option, return a map containing the single entry lst.collectEntries { [(it): it.toUpperCase()] } // [...

Apply the transformation to non-collection entries, delving into nested collections too and preserving the whole structure. def lst = ['foo', 'bar', ['inner_foo', 'inner_bar']] lst.collectNested { it.toUpperCase() } // [FOO, BAR, [INNER_FOO, INNER_BAR]]

def lst = ['foo', 'bar', ['inner_foo', 'inner_bar']] lst.flatten() ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​...

def lst = ['foo', 'foo', 'bar', 'baz'] // *modifies* the list removing duplicate items lst.unique() // [foo, bar, baz] // setting to false the "mutate" argument returns a new list, leaving the original intact lst.unique(false) // [foo, bar, baz] // convert the list to a Set, thu...

The Slow Query Log consists of log events for queries taking up to long_query_time seconds to finish. For instance, up to 10 seconds to complete. To see the time threshold currently set, issue the following: SELECT @@long_query_time; +-------------------+ | @@long_query_time | +-----------------...