大约有 46,000 项符合查询结果(耗时:0.0890秒) [XML]

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Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio

...t the solution specifically for the "opencases" column be simpler as just "select count(1)..." (or "count" of any other literal)? The Where clause already specifies "and closed is NULL" so no need for summing a case statement in this instance. Also, I've heard (aeons ago) that "count(*)" is not as e...
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How to see full query from SHOW PROCESSLIST

... pull the data and look at 'INFO' column which contains the whole query : select * from INFORMATION_SCHEMA.PROCESSLIST where db = 'somedb'; You can add any condition or ignore based on your requirement. The output of the query is resulted as : +-------+------+-----------------+--------+--------...
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Difference between View and table in sql

... A table contains data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database). The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database w...
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List of all index & index columns in SQL Server DB

...lumns. EDIT: This query's getting pretty close to what you're looking for: SELECT TableName = t.name, IndexName = ind.name, IndexId = ind.index_id, ColumnId = ic.index_column_id, ColumnName = col.name, ind.*, ic.*, col.* FROM sys.indexes ind INNER JOI...
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How to sleep for five seconds in a batch file/cmd [duplicate]

...specify the timeout in seconds and the /D parameter to specify the default selection and ignore then selected choice. The one thing that might be an issue is if the user types one of the choice characters before the timeout period elapses. A partial work-around is to obfuscate the situation -- use ...
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What is the difference between a stored procedure and a view?

...iece of SQL, I would define a view like: CREATE VIEW vw_user_profile AS SELECT A.user_id, B.profile_description FROM tbl_user A LEFT JOIN tbl_profile B ON A.user_id = b.user_id GO Thus, if I want to query profile_description by user_id in the future, all I have to do is: SELECT profile_descr...
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Linq to Entities join vs groupjoin

...Join syntax would be from p in Parent join c in Child on p.Id equals c.Id select new { p.Value, c.ChildValue } returning an IEnumerable<X> where X is an anonymous type with two properties, Value and ChildValue. This query syntax uses the Join method under the hood. GroupJoin syntax would be ...
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Convert text into number in MySQL query

... This should work: SELECT field,CONVERT(SUBSTRING_INDEX(field,'-',-1),UNSIGNED INTEGER) AS num FROM table ORDER BY num; share | improve this ...
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How to install Xcode Command Line Tools

... Xcode 5.1 and OSX 10.9. (also works with Xcode 5.1.1 + OSX 10.10) xcode-select --install worked with version 2333, failed with version 2003. So, try xcode-select --install and if that does not work download as described below. In early February 2014 xcode-select --install has been reporting that...
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Select all elements with “data-” attribute without using jQuery

Using only JavaScript, what is the most efficient way to select all DOM elements that have a certain data- attribute (let's say data-foo ). The elements may be different tag elements. ...