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Converting Select results into Insert script - SQL Server [closed]
...asier than installing plugins or external tools in some situations:
Do a select [whatever you need]INTO temp.table_namefrom [... etc ...].
Right-click on the database in the Object Explorer => Tasks => Generate Scripts
Select temp.table_name in the "Choose Objects" screen, click Next.
In the...
selecting unique values from a column
...
Use the DISTINCT operator in MySQL:
SELECT DISTINCT(Date) AS Date FROM buy ORDER BY Date DESC;
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Python pandas Filtering out nan from a data selection of a column of strings
... },
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LINQ to SQL: Multiple joins ON multiple Columns. Is this possible?
... from child in context.Childs
where child.Parent.col2 == 4
select new
{
childCol1 = child.col1,
parentCol1 = child.Parent.col1,
};
will generate the query
SELECT [t0].[col1] AS [childCol1], [t1].[col1] AS [parentCol1]
FROM [dbo].[Child] AS [...
Why does MYSQL higher LIMIT offset slow the query down?
...h more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
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How to alter SQL in “Edit Top 200 Rows” in SSMS 2008
...008 Management Studio, when I right click on a database table and choose " Select Top 100 Rows ", I can then e.g. easily add a "ORDER BY " statement to the SQL. That works fine .
...
The entity cannot be constructed in a LINQ to Entities query
... p in db.Products
where p.CategoryID == categoryID
select new ProductDTO { Name = p.Name }).ToList();
}
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Why can't I reference System.ComponentModel.DataAnnotations?
...odel.DataAnnotations assembly (Solution explorer -> Add reference -> Select .Net tab -> select System.ComponentModel.DataAnnotations from the list)
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SQLite UPSERT / UPDATE OR INSERT
... at this code:
INSERT INTO players (id, name, age)
VALUES (
coalesce((select id from players where user_name='steven'),
(select max(id) from drawings) + 1),
32)
The trick is in coalesce. It returns the id of the user 'steven' if any, and otherwise, it returns a new fresh id.
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select and update database record with a single queryset
How do I run an update and select statements on the same queryset rather than having to do two queries:
- one to select the object
- and one to update the object
...