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How do I get the MIN() of two fields in Postgres?
...
LEAST(a, b):
The GREATEST and LEAST functions select the largest or smallest value from a list of any number of expressions. The expressions must all be convertible to a common data type, which will be the type of the result (see Section 10.5 for details). NULL values in the list are ignored. T...
Check if a table exists in Rails
...? 'kittens'
In Rails 2, 3 & 4 the API is about tables.
# Listing of all tables and views
ActiveRecord::Base.connection.tables
# Checks for existence of kittens table/view (Kitten model)
ActiveRecord::Base.connection.table_exists? 'kittens'
Getting the status of migrations:
# Tells you all...
Definition of a Balanced Tree
...
The constraint is generally applied recursively to every subtree. That is, the tree is only balanced if:
The left and right subtrees' heights differ by at most one, AND
The left subtree is balanced, AND
The right subtree is balanced
According t...
StringFormat Localization issues in wpf
...rtup method.
– Björn
Jun 13 '13 at 11:29
18
Note that the Run element does not inherit from Fram...
When to use cla(), clf() or close() for clearing a plot in matplotlib?
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They all do different things, since matplotlib uses a hierarchical order in which a figure window contains a figure which may consist of many axes. Additionally, there are functions from the pyplot interface and there are methods ...
How do I copy directories recursively with gulp?
...c( [ files ], { "base" : "." }) can be used in the structure above to copy all the directories recursively.
If, like me, you may forget this then try:
gulp.copy=function(src,dest){
return gulp.src(src, {base:"."})
.pipe(gulp.dest(dest));
};
...
Xcode — what is $(SRCROOT)?
...ferent computer, so I need to update some paths. The library search paths all start with $(SRCROOT) . What does that mean?
...
How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
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SQL Server Profiler - How to filter trace to only display events from one database?
...ecific database? I can't see how to filter the trace to not see events for all databases on the instance I connect to.
5 An...
OAuth secrets in mobile apps
...ssue with the OAuth design that we are facing ourselves. We opted to proxy all calls through our own server. OAuth wasn't entirely flushed out in respect of desktop apps. There is no prefect solution to the issue that I've found without changing OAuth.
If you think about it and ask the question wh...