大约有 47,000 项符合查询结果(耗时:0.0391秒) [XML]

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Is Tomcat running?

...ave a diagnostics page with user load etc, you could fetch it periodically and parse it to determine if anything is going wrong. share | improve this answer | follow ...
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SQL Server Linked Server Example Query

...a Linked Server in SSMS Object Explorer, right-click, and Script Table as, SELECT To, and New Query Editor Window. The resulting SELECT statement will include the correct, fully-qualified path to the table. I had a mystery database qualifier in working with Sybase and this gave me the correct name. ...
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LINQ's Distinct() on a particular property

... (this IEnumerable<TSource> source, Func<TSource, TKey> keySelector) { HashSet<TKey> seenKeys = new HashSet<TKey>(); foreach (TSource element in source) { if (seenKeys.Add(keySelector(element))) { yield return element; } ...
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psql - save results of command to a file

...peruser privileges and will write to a file on the server. Example: COPY (SELECT foo, bar FROM baz) TO '/tmp/query.csv' (format csv, delimiter ';') Creates a CSV file with ';' as the field separator. As always, see the documentation for details ...
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How to add column if not exists on PostgreSQL?

...s, _col text, _type regtype) RETURNS bool AS $func$ BEGIN IF EXISTS (SELECT 1 FROM pg_attribute WHERE attrelid = _tbl AND attname = _col AND NOT attisdropped) THEN RETURN FALSE; ELSE EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
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MAMP Pro 3.05 on Mavericks updated to Yosemite - Apache does not start

... answered Oct 17 '14 at 10:56 AndreasAndreas 34811 gold badge33 silver badges99 bronze badges ...
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Drop data frame columns by name

...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it. ...
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Print a list of all installed node.js modules

...g on, I want to print all node.js modules (installed using npm) to the command line. How can I do this? 7 Answers ...
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Search text in fields in every table of a MySQL database

... If you have phpMyAdmin installed use its 'Search' feature. Select your DB Be sure you do have a DB selected (i.e. not a table, otherwise you'll get a completely different search dialog) Click 'Search' tab Choose the search term you want Choose the tables to search I have used this ...
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Save PL/pgSQL output from PostgreSQL to a CSV file

...e or automate, you can use Postgresql's built in COPY command. e.g. Copy (Select * From foo) To '/tmp/test.csv' With CSV DELIMITER ',' HEADER; This approach runs entirely on the remote server - it can't write to your local PC. It also needs to be run as a Postgres "superuser" (normally called "ro...