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MySQL select with CONCAT condition

....new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f5734570%2fmysql-select-with-concat-condition%23new-answer', 'question_page'); } ); Post as a guest ...
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SQL query to group by day

... (from Q8-Coder): GROUP BY dateadd(DAY,0, datediff(day,0, created)) For MySQL: GROUP BY year(datefield), month(datefield), day(datefield) or better (from Jon Bright): GROUP BY date(datefield) For Oracle: GROUP BY to_char(datefield, 'yyyy-mm-dd') or faster (from IronGoofy): GROUP BY trun...
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Best approach for designing F# libraries for use from both F# and C#

...tten in a functional style (using F# function types, tuples, discriminated unions etc.) .NET library is designed to be used from any .NET language (including C# and F#) and it typically follows .NET object-oriented style. This means that you'll expose most of the functionality as classes with method...
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GROUP_CONCAT ORDER BY

... @aleroot, Is this query MySQL specific? – Pacerier Apr 30 '15 at 20:24 ...
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How to do 3 table JOIN in UPDATE query?

...need a visual aid to get your joins correct: browse-tutorials.com/tutorial/mysql-joins-visual-representation – ram4nd Jan 27 '17 at 9:29 ...
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f

... @davidblaine, MySQL has a function GROUP_CONCAT() for that. dev.mysql.com/doc/refman/5.5/en/… But in standard SQL, each column should contain only one value. That's fundamental to relational theory too. – Bill Kar...
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常用Sql - 数据库(内核) - 清泛网 - 专注C/C++及内核技术

常用Sqlmysql:drop table if exists tablename;不能写成drop table tablename if exists tablename;mysql:建立索引SqlCREATE TABLE t...mysql:drop table if exists tablename; 不能写成 drop table tablename if exists tablename; mysql:建立索引Sql CREATE TABLE tablename ( `ID...
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PHP的函数前加上“@”的作用 - 更多技术 - 清泛网 - 专注C/C++及内核技术

...供的错误信息屏蔽的专用符号。比如在一个函数前使用@@mysql_query 不会出现Warning,而原来mysql_query 在遇到错误时会在页面上访提示Warning。@是PHP提供的错误信息屏蔽的专用符号。 比如在一个函数前使用@ @mysql_query 不会出现Warning...
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How to select the nth row in a SQL database table?

... http://troels.arvin.dk/db/rdbms/#select-limit. Basically, PostgreSQL and MySQL supports the non-standard: SELECT... LIMIT y OFFSET x Oracle, DB2 and MSSQL supports the standard windowing functions: SELECT * FROM ( SELECT ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber, columns F...
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What is the simplest SQL Query to find the second largest value?

... I see both some SQL Server specific and some MySQL specific solutions here, so you might want to clarify which database you need. Though if I had to guess I'd say SQL Server since this is trivial in MySQL. I also see some solutions that won't work because they fail to...