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mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
I am trying to select data from a MySQL table, but I get one of the following error messages:
31 Answers
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
... there are some info, especially about rsqrt (cpu is using internal lookup table with huge approximation, which makes it much simpler to get the result). It may seem, that rsqrt is so much faster than sqrt, that 1 additional mul operation (which isn't to costly) might not change the situation here. ...
Allowed characters in filename [closed]
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You should start with the Wikipedia Filename page. It has a decent-sized table (Comparison of filename limitations), listing the reserved characters for quite a lot of file systems.
It also has a plethora of other information about each file system, including reserved file names such as CON under...
Foreign keys in mongo?
...tions/referenced/1-n.html
In a NoSQL database like MongoDB there are not 'tables' but collections. Documents are grouped inside Collections. You can have any kind of document – with any kind of data – in a single collection. Basically, in a NoSQL database it is up to you to decide how to organi...
What is Lazy Loading?
...ded.
I.e. suppose you needed to have a record which has a join of several tables. If you fetched it all at once it would take longer than if you would fetch say only the main table. Using lazy-loading the rest of the information will be fetched only if it is needed. So it is actually 'efficient-loa...
Reducing the space between sections of the UITableView
Is there a way to reduce the space between two sections of a UITableView? There are about 15 pixels between every single section I have. I did already try to return 0 for -tableView:heightForFooterInSection: and -tableView:heightForHeaderInSection: but that doesn't change anything.
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Where does PostgreSQL store the database?
...ory;
To see all the run-time parameters, use
show all;
You can create tablespaces to store database objects in other parts of the filesystem. To see tablespaces, which might not be in that data directory, use this query.
SELECT * FROM pg_tablespace;
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PHP PDO: charset, set names?
...llation by clicking your database and choose operations. If you try create tables with another collation than your database, your tables will end up with the database collation anyways.
So make sure the collation for your database is right before creating tables. Hope this saves someone a few hours...
How to prevent a background process from being stopped after closing SSH client in Linux
...-ar] [jobspec ...]
By default, removes each JOBSPEC argument from the table of active jobs.
If the -h option is given, the job is not removed from the table, but is
marked so that SIGHUP is not sent to the job if the shell receives a
SIGHUP. The -a option, when JOBSPEC is not suppl...
PostgreSQL naming conventions
Where can I find a detailed manual about PostgreSQL naming conventions? (table names vs. camel case, sequences, primary keys, constraints, indexes, etc...)
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