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Strings as Primary Keys in SQL Database [closed]
... I would agree there are a lot of variables to consider. (In sqlserver) we have seen real performance issues with using strings with lengths in the mid to high teens and above even when indexed. Buy you're right there are things to overcome this hardware for instance.
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How to query as GROUP BY in django?
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An easy solution, but not the proper way is to use raw SQL:
results = Members.objects.raw('SELECT * FROM myapp_members GROUP BY designation')
Another solution is to use the group_by property:
query = Members.objects.all().query
query.group_by = ['designation']
results = Query...
SQL set values of one column equal to values of another column in the same table
....new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f7817007%2fsql-set-values-of-one-column-equal-to-values-of-another-column-in-the-same-table%23new-answer', 'question_page');
}
);
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How do you create a Distinct query in HQL
...is a valid keywork for HQL, but I am looking for the HQL equivalent of the SQL keyword "distinct".
11 Answers
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insert a NOT NULL column to an existing table
...swer above contains GO which is a must when you run this code on Microsoft SQL server. If you want to perform the same operation on Oracle or MySQL you need to use semicolon ; like that:
ALTER TABLE MY_TABLE ADD STAGE INT NULL;
UPDATE MY_TABLE SET <a valid not null values for your column>;
AL...
SQL Server 2008: How to query all databases sizes?
I have MS SQL 2008 R2, 500 databases.
What is the most efficient, easiest and 'modern' way to query all databases sizes.
14...
Python/postgres/psycopg2: getting ID of row just inserted
...URNING id")
id_of_new_row = cursor.fetchone()[0]
And please do not build SQL strings containing values manually. You can (and should!) pass values separately, making it unnecessary to escape and SQL injection impossible:
sql_string = "INSERT INTO domes_hundred (name,name_slug,status) VALUES (%s,%...
SQL Server: converting UniqueIdentifier to string in a case statement
....new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f6299918%2fsql-server-converting-uniqueidentifier-to-string-in-a-case-statement%23new-answer', 'question_page');
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VC菜单命令详解(文件打开、保存与关闭) - C/C++ - 清泛网 - 专注C/C++及内核技术
...构造the main frame对象和the main frame window，但不显示它，它包括IDR_MAINFRAME、the toolbar、the status bar；
3、构造view对象和view窗口，但不显示它；
4、建立the document、main frame、view对象之间的关系，这里要借助AddDocTemplate建立的类关系...
Manually map column names with class properties
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This works fine:
var sql = @"select top 1 person_id PersonId, first_name FirstName, last_name LastName from Person";
using (var conn = ConnectionFactory.GetConnection())
{
var person = conn.Query<Person>(sql).ToList();
return person...