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Find the number of columns in a table
It is possible to find the number of rows in a table:
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Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...t mix collations, so you have four options:
Option 1: add COLLATE to your input variable:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @rProductID, @rPerm);
Option 2: add COLLATE to the WHERE clause:
CREATE PROCEDURE updateProductUse...
How to efficiently build a tree from a flat structure?
I have a bunch of objects in a flat structure. These objects have an ID and a ParentID property so they can be arranged in trees. They are in no particular order.
Each ParentID property does not necessarily matches with an ID in the structure. Therefore their could be several trees emerging ...
How to switch between hide and view password
...s there a clever way to let the user switch between hide and view password in an android EditText?
A number of PC based apps let the user do this.
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What's the difference between Unicode and UTF-8? [duplicate]
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most editors support save as ‘Unicode’ encoding actually.
This is an unfortunate misnaming perpetrated by Windows.
Because Windows uses UTF-16LE encoding internally as the memory storage format for Unicode strings, it considers this to be the natural encoding of Uni...
How can I convert a string to boolean in JavaScript?
Can I convert a string representing a boolean value (e.g., 'true', 'false') into a intrinsic type in JavaScript?
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Remove unnecessary svn:mergeinfo properties
When I merge stuff in my repository Subversion wants to add/change a lot of svn:mergeinfo properties to files that are totally unrelated to the things that I want to merge.
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Parsing JSON Object in Java [duplicate]
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I'm assuming you want to store the interestKeys in a list.
Using the org.json library:
JSONObject obj = new JSONObject("{interests : [{interestKey:Dogs}, {interestKey:Cats}]}");
List<String> list = new ArrayList<String>...
performSelector may cause a leak because its selector is unknown
I'm getting the following warning by the ARC compiler:
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When do I really need to use atomic instead of bool? [duplicate]
...tomic<bool> redundant because bool is atomic by nature? I don't think it's possible to have a partially modified bool value. When do I really need to use atomic<bool> instead of bool ?
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