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MySQL: Invalid use of group function
..., not WHERE.
The difference is: the WHERE clause filters which rows MySQL selects. Then MySQL groups the rows together and aggregates the numbers for your COUNT function.
HAVING is like WHERE, only it happens after the COUNT value has been computed, so it'll work as you expect. Rewrite your subque...
Why do I get “Procedure expects parameter '@statement' of type 'ntext/nchar/nvarchar'.” when I try t
...r because @SQL needs to be NVARCHAR
DECLARE @SQL VARCHAR(100)
SET @SQL = 'SELECT TOP 1 * FROM sys.tables'
EXECUTE sp_executesql @SQL
So:
DECLARE @SQL NVARCHAR(100)
SET @SQL = 'SELECT TOP 1 * FROM sys.tables'
EXECUTE sp_executesql @SQL
...
How to wait for all goroutines to finish without using time.Sleep?
This code selects all xml files in the same folder, as the invoked executable and asynchronously applies processing to each result in the callback method (in the example below, just the name of the file is printed out).
...
How can I use grep to show just filenames on Linux?
...andard:
-l
(The letter ell.) Write only the names of files containing selected
lines to standard output. Pathnames are written once per file searched.
If the standard input is searched, a pathname of (standard input) will
be written, in the POSIX locale. In other locales, standard i...
Really Cheap Command-Line Option Parsing in Ruby
...y chairs are in the classroom", :default => 1
p.option :room_number, "select room number", :default => 2, :value_in_set => [1,2,3,4]
end.process!
Calling the script with -h or --help will print
Usage: micro-optparse-example [options]
-v, --[no-]verbose turn on verbose...
Font Awesome icon inside text input element
...e placeholder attribute will simply ignore it.
UPDATE
The before content selector selects the input: input[type="text"]:before. You should select the wrapper: .wrapper:before. See http://jsfiddle.net/allcaps/gA4rx/ .
I also added the placeholder suggestion where the wrapper is redundant.
.wrap...
Can scrapy be used to scrape dynamic content from websites that are using AJAX?
...om scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import HtmlXPathSelector
from scrapy.http import Request
from selenium import selenium
class SeleniumSpider(CrawlSpider):
name = "SeleniumSpider"
start_urls = ["http://www.domain.com"]
rules = (
...
Blocks and yields in Ruby
...y:
days = ["monday", "tuesday", "wednesday", "thursday", "friday"]
# select those which start with 't'
days.select do | item |
item.match /^t/
end
=> ["tuesday", "thursday"]
Or, we can also provide a custom sort algorithm, for instance based on the string size:
days.sort do |x,...
In Intellij, how do I toggle between camel case and underscore spaced?
...g Manipulation which has the capabilities you're looking for (and more).
Select historyOfPresentIllness and press Alt+M to bring up the plugin menu, then press:
5 - To snake_case (or to camelCase) which converts to history_of_present_illness
6 - To hyphen-case (or to snake_case) which converts...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...t have to have a placeholder for it in the Insert statement. Then a simple select * into the target table auto populated this column. Here are the two SQL statements that I used on PostgreSQL 9.6.4.
ALTER TABLE target ADD COLUMN some_column SERIAL;
INSERT INTO target SELECT * from source;
...