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PostgreSQL: Drop PostgreSQL database through command line [closed]

...rrently taking place against your database, including all idle processes. SELECT * FROM pg_stat_activity WHERE datname='database name'; share | improve this answer | follow...
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MySQL - force not to use cache for testing speed of query

...ACHE (MySQL 5.7) option in your query. (MySQL 5.6 users click HERE ) eg. SELECT SQL_NO_CACHE * FROM TABLE This will stop MySQL caching the results, however be aware that other OS and disk caches may also impact performance. These are harder to get around. ...
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Default filter in Django admin

...lookup, title in self.lookup_choices: yield { 'selected': self.value() == lookup, 'query_string': cl.get_query_string({ self.parameter_name: lookup, }, []), 'display': title, } def querys...
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How to check if an element does NOT have a specific class?

...t one for the case in the question, but just as a reference if you need to select elements that don't have a certain class, you can use the not selector: // select all divs that don't have class test $( 'div' ).not( ".test" ); $( 'div:not(.test)' ); // <-- alternative ...
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String.Join method that ignores empty strings?

... simpler, since you can do it in SQL directly: PostgreSQL & MySQL: SELECT concat_ws(' / ' , NULLIF(searchTerm1, '') , NULLIF(searchTerm2, '') , NULLIF(searchTerm3, '') , NULLIF(searchTerm4, '') ) AS RPT_SearchTerms; And even with the glorious MS-SQ...
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SQL query for today's date minus two months

I want to select all the records in a table where their date of entry is older then 2 months. 5 Answers ...
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ERROR: permission denied for sequence cities_id_seq using Postgres

... Since PostgreSQL 8.2 you have to use: GRANT USAGE, SELECT ON SEQUENCE cities_id_seq TO www; GRANT USAGE - For sequences, this privilege allows the use of the currval and nextval functions. Also as pointed out by @epic_fil in the comments you can grant permissions to all th...
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LAST_INSERT_ID() MySQL

...RT INTO table2 (parentid,otherid,userid) VALUES (LAST_INSERT_ID(), 4, 1); SELECT MAX(id) FROM table1; share | improve this answer | follow | ...
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Possible to perform cross-database queries with PostgreSQL?

... executes a query in a remote database dblink executes a query (usually a SELECT, but it can be any SQL statement that returns rows) in a remote database. When two text arguments are given, the first one is first looked up as a persistent connection's name; if found, the command is executed on that...
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Limit file format when using ?

...te of <input type = "file"> can help to provide a filter in the file select dialog box of the OS. For example, <!-- (IE 10+, Edge (EdgeHTML), Edge (Chromium), Chrome, Firefox 42+) --> <input type="file" accept=".xls,.xlsx" /> should provide a way to filter out files other...