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Is there a better way to dynamically build an SQL WHERE clause than by using 1=1 at its beginning?

... {2}", clause, appender, condition); } Use it like this string query = "SELECT * FROM Table1 {0}"; string whereClause = string.Empty; if (condition 1) whereClause = AddCondition(whereClause, "AND", "Col=1"); if (condition 2) whereClause = AddCondition(whereClause, "AND", "Col2=2"); str...
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How to report an error from a SQL Server user-defined function

... For an inline-table-valued-function where the RETURN is a simple select, this alone doesn't work because nothing is returned - not even null, and in my case I wanted to throw an error when nothing was found. I didn't want to break down the inline function into a multi-statment one for obv...
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Retrieve the maximum length of a VARCHAR column in SQL Server

... Use the built-in functions for length and max on the description column: SELECT MAX(LEN(DESC)) FROM table_name; Note that if your table is very large, there can be performance issues. share | im...
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select、poll、epoll之间的区别总结[整理] - C/C++ - 清泛网 - 专注C/C++及内核技术

select、poll、epoll之间的区别总结[整理]select,poll,epoll都是IO多路复用的机制。I O多路复用就通过一种机制,可以监视多个描述符,一旦某个描述符就绪(一般是读就绪或者写就绪...select,poll,epoll都是IO多路复用的机制。I/O多路...
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How to get first and last day of previous month (with timestamp) in SQL Server

... select DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0) --First day of previous month select DATEADD(MONTH, DATEDIFF(MONTH, -1, GETDATE())-1, -1) --Last Day of previous month ...
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MySQL Orderby a number, Nulls last

...Place a minus sign (-) before the column name and switch the ASC to DESC: SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC. A good reference is here http://t...
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Convert INT to VARCHAR SQL

I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error: ...
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Removing leading zeroes from a field in a SQL statement

... VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the data as '1A'. ...
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Query grants for a table in postgres

... I already found it: SELECT grantee, privilege_type FROM information_schema.role_table_grants WHERE table_name='mytable' share | improve this...
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How to call a PHP function on the click of a button

..."insert" value="insert" /> <input type="submit" class="button" name="select" value="select" />   jQuery: $(document).ready(function(){ $('.button').click(function(){ var clickBtnValue = $(this).val(); var ajaxurl = 'ajax.php', data = {'action': clickBtnValu...