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Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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Psql list all tables
...This is where the INFORMATION_SCHEMA comes to the rescue. To list tables:
SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';
BTW, if you ever want to see what psql is doing in response to a backslash command, run psql with the -E flag. eg:
$ psql -E regress
regre...
PostgreSQL: How to make “case-insensitive” query
...unction to convert the strings to lower case before comparing.
Try this:
SELECT id
FROM groups
WHERE LOWER(name)=LOWER('Administrator')
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How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...
java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
... a query, specifically the position where a reader is in a ResultSet. Each SELECT statement has a cursor, and PL/SQL stored procedures can open and use as many cursors as they require. You can find out more about cursors on Orafaq.
A database instance typically serves several different schemas, man...
How do I reformat HTML code using Sublime Text 2?
...
You don't need any plugins to do this.
Just select all lines (Ctrl A) and then from the menu select Edit → Line → Reindent.
This will work if your file is saved with an extension that contains HTML like .html or .php.
If you do this often, you may find this key ma...
Android studio add external project to build.gradle
...ick module -> Open Module Settings -> Dependencies -> + (bottom), select Module Dependency, select your library from the list, click ok :)
– T.Coutlakis
Jan 11 '15 at 22:51
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Can you use an alias in the WHERE clause in mysql?
...ts an unknown column. Is there any way to get around this issue? I need to select records that have a rating higher than x. Rating is calculated as the following alias:
...
Using TortoiseSVN via the command line
...ssociated with it. But on the installer (of version 1.7 and later) you can select the "command line client tools" option so you can call svn commands (like svn commit and svn update) from the command line.
Here's a screenshot of the "command line client tools" option in the installer, you need to m...
MySQL indexes - what are the best practices?
...t them. Generally I put an index on any fields that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
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