大约有 44,000 项符合查询结果(耗时:0.0511秒) [XML]

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Java: method to get position of a match in a String?

... First loop will fail to find all positions if matching one char. You don't need +1 in for loop second statement, because third statement does counting i++ try for String text = "0011100"; matching word char "1" it will print 2,4 not 2,3,4 – Strauteka ...
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How do I (or can I) SELECT DISTINCT on multiple columns?

... SELECT DISTINCT a,b,c FROM t is roughly equivalent to: SELECT a,b,c FROM t GROUP BY a,b,c It's a good idea to get used to the GROUP BY syntax, as it's more powerful. For your query, I'd do it like this: UPDATE sale...
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Database Design for Tagging

... to rebuilt every time a question has a tag added or removed. A query like select * from question q inner join question_has_tag qt where tag_id in (select tag_id from tags where (what we want) minus select tag_id from tags where (what we don't) should be fine and scale out assuming the right b-tree ...
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What does it mean by select 1 from table?

... SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, c...
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INSERT IF NOT EXISTS ELSE UPDATE?

...ike: insert or replace into Book (ID, Name, TypeID, Level, Seen) values ((select ID from Book where Name = "SearchName"), "SearchName", ...); Note that any field not in the insert list will be set to NULL if the row already exists in the table. This is why there's a subselect for the ID column: I...
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postgresql return 0 if returned value is null

...eved for display. Edit Here's an example of COALESCE with your query: SELECT AVG( price ) FROM( SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan WHERE listing_Type = 'AARM' AND u_kbalikepartnumbers_id = 1000307 AND ( EXTRACT( DAY FROM ( NOW() - ...
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Select top 10 records for each category

... If you are using SQL 2005 you can do something like this... SELECT rs.Field1,rs.Field2 FROM ( SELECT Field1,Field2, Rank() over (Partition BY Section ORDER BY RankCriteria DESC ) AS Rank FROM table ) rs WHERE Rank <= 10 If y...
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How to add a line break in an Android TextView?

... i just wanted to add that this quote-stuff also works fine with special characters in string resources or with languages like greek or russian... (if you encounter any problems) – datayeah Jun 19 '12 at 10:09 ...
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How to see query history in SQL Server Management Studio

...been evicted, etc.), you may be able to find the query in the plan cache. SELECT t.[text] FROM sys.dm_exec_cached_plans AS p CROSS APPLY sys.dm_exec_sql_text(p.plan_handle) AS t WHERE t.[text] LIKE N'%something unique about your query%'; If you lost the file because Management Studio crashed, you...
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NOT IN vs NOT EXISTS

...llow NULLs the NOT IN will be treated identically to the following query. SELECT ProductID, ProductName FROM Products p WHERE NOT EXISTS (SELECT * FROM [Order Details] od WHERE p.ProductId = od.ProductId) The exact plan may vary but for my examp...