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how can I Update top 100 records in sql server
I want to update the top 100 records in SQL Server. I have a table T1 with fields F1 and F2 . T1 has 200 records. I want to update the F1 field in the top 100 records. How can I update based on TOP 100 in SQL Server?
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SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
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Cascade will work when you delete something on table Courses. Any record on table BookCourses that has reference to table Courses will be deleted automatically.
But when you try to delete on table BookCourses only the table itself is affected and not on the Courses
foll...
B-Tree vs Hash Table
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You can only access elements by their primary key in a hashtable.
This is faster than with a tree algorithm (O(1) instead of log(n)), but you cannot select ranges (everything in between x and y).
Tree algorithms support this in Log(n) whereas hash indexes can result in a full table s...
select into in mysql
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Use the CREATE TABLE SELECT syntax.
http://dev.mysql.com/doc/refman/5.0/en/create-table-select.html
CREATE TABLE new_tbl SELECT * FROM orig_tbl;
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LINQ to SQL Left Outer Join
..."left" row in a left-outer-join will match 0-n "right" rows (in the second table), where-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o...
Difference Between Schema / Database in MySQL
...racle Database product, a schema represents only a part of a database: the tables and other objects owned by a single user.
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What's the purpose of SQL keyword “AS”?
You can set table aliases in SQL typing the identifier right after the table name.
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How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
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Do I need to create indexes on foreign keys on Oracle?
I have a table A and a table B . A has a foreign key to B on B 's primary key, B_ID .
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Get Insert Statement for existing row in MySQL
...ut you can get them using mysqldump like Rob suggested. Specify -t to omit table creation.
mysqldump -t -u MyUserName -pMyPassword MyDatabase MyTable --where="ID = 10"
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