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String concatenation in MySQL
...most DBMSs use of + or || for concatenation. It uses the CONCAT function:
SELECT CONCAT(first_name, " ", last_name) AS Name FROM test.student
As @eggyal pointed out in comments, you can enable string concatenation with the || operator in MySQL by setting the PIPES_AS_CONCAT SQL mode.
...
How to import an excel file in to a MySQL database
...r Excel table into the sales table of a MySQL database named mydatabase.
Select the relevant cells:
Paste into Mr. Data Converter and select the output as MySQL:
Change the table name and column definitions to fit your requirements in the generated output:
CREATE TABLE sales (
id INT NOT N...
Is there a MySQL option/feature to track history of changes to records?
...i AFTER INSERT ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'insert', NULL, NOW(), d.*
FROM MyDB.data AS d WHERE d.primary_key_column = NEW.primary_key_column;
CREATE TRIGGER MyDB.data__au AFTER UPDATE ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'up...
Notepad++ - How can I replace blank lines [duplicate]
...
Press Ctrl+H (Replace)
Select Extended from SearchMode
Put \r\n\r\n in Find What
Put \r\n in ReplaceWith
Click on Replace All
share
|
improve t...
How to avoid null checking in Java?
...t that it cannot be null, and that's it.
Example:
public String getFirst3Chars(String text) {
return text.subString(0, 3);
}
However, if your method just passes the value on, and the next method passes it on etc. it could get problematic. In that case you may want to check the argument as abov...
Cannot create or edit Android Virtual Devices (AVD) from Eclipse, ADT 22.6
...lone button worked and I was able to successfully edit the clone.
Steps:
Select a Device by Google
Click the "Clone..." button
A window will pop up, click "Clone device"
Select the newly cloned Device, it should say "... by User"
Click the "Edit" button on the side
There you have it...
Programmatically trigger “select file” dialog box
I have a hidden file input element. Is it possible to trigger its select file dialog box from a button's click event?
13 ...
List comprehension in Ruby
..._ARRAY.map{|x| x % 2 == 0 ? x * 3 : nil}.compact
end
end
def test_select_map
1000.times do
TEST_ARRAY.select{|x| x % 2 == 0 }.map{|x| x * 3}
end
end
def test_inject
1000.times do
TEST_ARRAY.inject([]) {|all, x| all << x*3 if x % 2 == 0; all }
end
end...
How to solve “The specified service has been marked for deletion” error
...ing state. The following procedure worked for me:
open task manager > select services tab > select the service > right click and select "go to process" > right click on the process and select End process
Service should be gone after that
...
Transaction isolation levels relation with locks on table
... writes data and commit/rollback (depending on results). B just executes a SELECT statement to read data. C reads and updates data. All these process work on the same table T.
READ UNCOMMITTED - no lock on the table. You can read data in the table while writing on it. This means A writes data (unc...