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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
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@davidblaine, MySQL has a function GROUP_CONCAT() for that. dev.mysql.com/doc/refman/5.5/en/… But in standard SQL, each column should contain only one value. That's fundamental to relational theory too.
– Bill Kar...
What is the difference between single and double quotes in SQL?
...ct_id
SELECT PRODUCT.id 'product_id'
Either works in Oracle, SQL Server, MySQL… but I know some have said that the TOAD IDE seems to give some grief when using the single quotes approach.
You do have to use single quotes when the column alias includes a space character, e.g., product id, but it...
How to print SQL statement in codeigniter model
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Fatal error: Call to undefined method CI_DB_mysql_driver::get_compiled_select()
– itskawsar
Sep 25 '13 at 8:53
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MySQL Select Query - Get only first 10 characters of a value
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Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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How to get ER model of database from server with Workbench
...y to get an ER model of a database from the server that is connected to my MySQL Workbench?
4 Answers
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PHP_SELF vs PATH_INFO vs SCRIPT_NAME vs REQUEST_URI
... The filename of the currently executing script, relative to the document root. For instance, $_SERVER['PHP_SELF'] in a script at the address http://example.com/test.php/foo.bar would be /test.php/foo.bar. The __FILE__ constant contains the full path and filename of the current (i.e. included) file...
MySQL, better to insert NULL or empty string?
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Better to Insert NULL for consistency in your database in MySQL. Foreign keys can be stored as NULL but NOT as empty strings.
You will have issues with an empty string in the constraints.
You may have to insert a fake record with a unique empty string to satisfy a Foreign Key cons...
Mathematical functions in Swift
... sqrt, floor and round because you may natively use respectively 0.5.squareRoot(), Int(0.5) and 0.5.round().
– Cœur
Oct 10 '18 at 10:04
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MySQL: Selecting multiple fields into multiple variables in a stored procedure
...T multiple columns into multiple variables within the same select query in MySQL?
3 Answers
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Datetime equal or greater than today in MySQL
...Date) = DATE(NOW())
Read more:
http://www.tomjepson.co.uk/tutorials/36/mysql-select-where-date-today.html
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