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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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generate days from date range
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This solution uses no loops, procedures, or temp tables. The subquery generates dates for the last 10,000 days, and could be extended to go as far back or forward as you wish.
select a.Date
from (
select curdate() - INTERVAL (a.a + (10 * b.a) + (100 * c.a) + (1000 * d...
How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
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How do I migrate a model out of one django app and into a new one?
...rd code
#to use just one sentence:
def forwards(self, orm):
db.rename_table('common_cat', 'specific_cat')
if not db.dry_run:
# For permissions to work properly after migrating
orm['contenttypes.contenttype'].objects.filter(
app_label='common',
model...
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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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...
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...
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...
How to create composite primary key in SQL Server 2008
I want to create tables in SQL Server 2008, but I don't know how to create composite primary key. How can I achieve this?
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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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