大约有 42,000 项符合查询结果(耗时:0.0287秒) [XML]

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MySQL - length() vs char_length()

... in two bytes. Or UTF-8, where the number of bytes varies. For example: select length(_utf8 '€'), char_length(_utf8 '€') --> 3, 1 As you can see the Euro sign occupies 3 bytes (it's encoded as 0xE282AC in UTF-8) even though it's only one character. ...
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How to convert an entire MySQL database characterset and collation to UTF-8?

... You can create the sql to update all tables with: SELECT CONCAT("ALTER TABLE ",TABLE_SCHEMA,".",TABLE_NAME," CHARACTER SET utf8 COLLATE utf8_general_ci; ", "ALTER TABLE ",TABLE_SCHEMA,".",TABLE_NAME," CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci; ") AS a...
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How to create a SQL Server function to “join” multiple rows from a subquery into a single delimited

... If you're using SQL Server 2005, you could use the FOR XML PATH command. SELECT [VehicleID] , [Name] , (STUFF((SELECT CAST(', ' + [City] AS VARCHAR(MAX)) FROM [Location] WHERE (VehicleID = Vehicle.VehicleID) FOR XML PATH ('')), 1, 2, '')) AS Locations FROM [...
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C#: how to get first char of a string?

... Select the oldest tab to see that it as Matthew – johnc Oct 7 '10 at 5:10 11 ...
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SQL Server 2008: How to query all databases sizes?

... with fs as ( select database_id, type, size * 8.0 / 1024 size from sys.master_files ) select name, (select sum(size) from fs where type = 0 and fs.database_id = db.database_id) DataFileSizeMB, (select sum(size) from fs wh...
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Oracle中translate与replace的使用 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术

Oracle中translate与replace的使用SELECT TRANSLATE(& 39;,abcdefghij,& 39;,& 39;,jabcdefghi& 39;,& 39;+& 39;) FROM dual; --第二、三参数一一对应,没有对应就删除原 SELECT TRANSLATE(',abc,', ',cab', '+') FROM dual; --结果:++ SELECT TRANSLATE(',abc,', 'cab,', '+') FROM dual; ...
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Insert Update trigger how to determine if insert or update

... track "before" and "after" data. So you can use something like IF EXISTS (SELECT * FROM DELETED) to detect an update. You only have rows in DELETED on update, but there are always rows in INSERTED. Look for "inserted" in CREATE TRIGGER. Edit, 23 Nov 2011 After comment, this answer is only for INSER...
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Convert HashBytes to VarChar

... I have found the solution else where: SELECT SUBSTRING(master.dbo.fn_varbintohexstr(HashBytes('MD5', 'HelloWorld')), 3, 32) share | improve this answer ...
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Replacing a char at a given index in string? [duplicate]

... return value; else return string.Concat(value.Select((c, i) => i == index ? newchar : c)); } } and then, for example: string instr = "Replace$dollar"; string outstr = instr.ReplaceAt(7, ' '); In the end I needed to utilize .Net Framework 2, so I use a StringB...
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Hidden Features of MySQL

...that has an integer type, you can also refer to the column as "_rowid" in SELECT statements. In MySQL, the name of a PRIMARY KEY is PRIMARY Currently, only InnoDB (v5.1?) tables support foreign keys. Usually, you create all the indexes you need when you are creating tables. Any column declared...