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MySQL SELECT only not null values
...WHERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
Edited to reflect comments. It sounds like your table may not be in first ...
MySQL combine two columns into one column
...
My guess is that you are using MySQL where the + operator does addition, along with silent conversion of the values to numbers. If a value does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two way...
How to use GROUP BY to concatenate strings in MySQL?
... id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string result with the concatenated non-NULL values from a group. It returns NULL if there ...
Alter a MySQL column to be AUTO_INCREMENT
...ber between parenthesis does exactly nothing (well ok, almost nothing) for MySQL integer types. The only thing that may be influenced by the number is the display width, and it is up to the client to do that. But don't be deceived and think that it works like it does for VARCHAR and DECIMAL types - ...
tinyxml XML解析库下载（tinyxml2.h 和 tinyxml2.cpp） - 源码下载 - 清泛...
...int SIZE >
class MemPoolT : public MemPool
{
public:
MemPoolT() : _root(0), _currentAllocs(0), _nAllocs(0), _maxAllocs(0), _nUntracked(0) {}
~MemPoolT() {
// Delete the blocks.
for( int i=0; i<_blockPtrs.Size(); ++i ) {
delete _blockPtrs[i];
}
...
Create a CSV File for a user in PHP
I have data in a MySQL database. I am sending the user a URL to get their data out as a CSV file.
19 Answers
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What does it mean when MySQL is in the state “Sending data”?
What does it mean if the Mysql query:
2 Answers
2
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MySQL Like multiple values
I have this MySQL query.
9 Answers
9
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Why is MySQL's default collation latin1_swedish_ci?
...rs? they changed this into a sane default, like utf8_general_ci. Good job, MySQL !
– Michael Trouw
Sep 24 '15 at 10:17
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Python executable not finding libpython shared library
...ce configure directives to handle alternate library paths (not everyone is root you know...) In the simplest case all you need is the following:
./configure --enable-shared \
--prefix=/usr/local \
LDFLAGS="-Wl,--rpath=/usr/local/lib"
Or if you prefer the non-linux version...