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What's the difference between utf8_general_ci and utf8_unicode_ci?
...or "ǽ" == "æ". For sorting this makes sense but could be surprising when selecting via equalities or dealing with unique indices - bugs.mysql.com/bug.php?id=16526
– Mat Schaffer
Mar 13 '15 at 15:22
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How can I remove duplicate rows?
...
Assuming no nulls, you GROUP BY the unique columns, and SELECT the MIN (or MAX) RowId as the row to keep. Then, just delete everything that didn't have a row id:
DELETE FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3
FROM MyTable
GROUP BY Co...
How do I search within an array of hashes by hash values in ruby?
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You're looking for Enumerable#select (also called find_all):
@fathers.select {|father| father["age"] > 35 }
# => [ { "age" => 40, "father" => "Bob" },
# { "age" => 50, "father" => "Batman" } ]
Per the documentation, it "returns a...
JPA and Hibernate - Criteria vs. JPQL or HQL
...oaded. This means one Criteria query might result in several SQL immediate SELECT statements to fetch the subgraph with all non-lazy mapped associations and collections. If you want to change the "how" and even the "what", use setFetchMode() to enable or disable outer join fetching for a particular ...
How to convert float to varchar in SQL Server
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Try using the STR() function.
SELECT STR(float_field, 25, 5)
STR() Function
Another note: this pads on the left with spaces. If this is a problem combine with LTRIM:
SELECT LTRIM(STR(float_field, 25, 5))
...
How do I get the current time zone of MySQL?
...bal and client-specific time zones can be retrieved like this:
mysql> SELECT @@global.time_zone, @@session.time_zone;
Edit The above returns SYSTEM if MySQL is set to slave to the system's timezone, which is less than helpful. Since you're using PHP, if the answer from MySQL is SYSTEM, you ca...
Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...ps for adding external jars in IntelliJ IDEA:
Click File from the toolbar
Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X)
Select Modules at the left panel
Select Dependencies tab
Select + icon
Select 1 JARs or directories option
...
Psql list all tables
...This is where the INFORMATION_SCHEMA comes to the rescue. To list tables:
SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';
BTW, if you ever want to see what psql is doing in response to a backslash command, run psql with the -E flag. eg:
$ psql -E regress
regre...
Check if table exists in SQL Server
...nge from version to version.
To check if a table exists use:
IF (EXISTS (SELECT *
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'TheSchema'
AND TABLE_NAME = 'TheTable'))
BEGIN
--Do Stuff
END
...
Visual Studio: How to break on handled exceptions?
...the VS2010 environement, by going to "Tools", "Import Export Settings" and select a reset to the C# environment... it contains the Exceptions Submenu item
– BeardinaSuit
Feb 14 '12 at 16:28
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