大约有 3,551 项符合查询结果（耗时：0.0245秒） [XML]
Find all records which have a count of an association greater than zero
...inct.size
=> 17
[14] pry(main)> Article.joins(:comments).distinct.to_sql
=> "SELECT DISTINCT \"articles\".* FROM \"articles\" INNER JOIN \"comments\" ON \"comments\".\"article_id\" = \"articles\".\"id\""
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Targeting both 32bit and 64bit with Visual Studio in same solution/project
...istered in the GAC, you can also use the standard reference tags this way (SQLite as an example):
<ItemGroup Condition="'$(Platform)' == 'x86'">
<Reference Include="System.Data.SQLite, Version=1.0.80.0, Culture=neutral, PublicKeyToken=db937bc2d44ff139, processorArchitecture=x86" />
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Search of table names
...DBName.sys.tables
WHERE Name LIKE '%XXX%'
If so, you could use dynamic SQL to add the dbname to the query:
DECLARE @DBName NVARCHAR(200) = 'YourDBName',
@TableName NVARCHAR(200) = 'SomeString';
IF NOT EXISTS (SELECT 1 FROM master.sys.databases WHERE Name = @DBName)
BEGIN
PR...
Select columns from result set of stored procedure
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This was interesting: sqlnerd.blogspot.com/2005/09/…
– d-_-b
Mar 4 '12 at 23:40
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Does the join order matter in SQL?
... In fact, all join types are associative, as specified by the SQL standard and according to mathematical definitions of associativity, but they don't appear associative because rearranging the parentheses requires moving the ON clause (i.e. the "join specification") to a new location. T...
SQLite add Primary Key
I created a table in Sqlite by using the CREATE TABLE AS syntax to create a table based on a SELECT statement. Now this table has no primary key but I would like to add one.
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How can I get the actual stored procedure line number from an error message?
When I use SQL Server and there's an error, the error message gives a line number that has no correlation to the line numbers in the stored procedure. I assume that the difference is due to white space and comments, but is it really?
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Select all columns except one in MySQL?
...rying to use a select statement to get all of the columns from a certain MySQL table except one. Is there a simple way to do this?
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MySQL combine two columns into one column
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My guess is that you are using MySQL where the + operator does addition, along with silent conversion of the values to numbers. If a value does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two ways ...
Get the new record primary key ID from MySQL insert query?
Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
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