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Export database schema into SQL file
...ht click the database you want to generate scripts for (not the table) and select tasks - generate scripts
Next, select the requested table/tables, views, stored procedures, etc (from select specific database objects)
Click advanced - select the types of data to script
Click Next and finish
MSDN...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
...
Android ListView with different layouts for each row
...g provided.
A ListView can support multiple row styles because it derives from AdapterView:
An AdapterView is a view whose children are determined by an Adapter.
If you look at the Adapter, you'll see methods that account for using row-specific views:
abstract int getViewTypeCount()
// Retur...
MySQL select 10 random rows from 600K rows fast
How can I best write a query that selects 10 rows randomly from a total of 600k?
26 Answers
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How to get multiple counts with one SQL query?
...tion. This is basically the same thing as a PIVOT function in some RDBMS:
SELECT distributor_id,
count(*) AS total,
sum(case when level = 'exec' then 1 else 0 end) AS ExecCount,
sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
...
MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
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How to select only 1 row from oracle sql?
I want to use oracle syntax to select only 1 row from table DUAL . For example, I want to execute this query:
13 Answers
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Should MySQL have its timezone set to UTC?
...the timezone will not change the stored datetime or
timestamp, but it will select a different datetime from
timestamp columns
Warning! UTC has leap seconds, these look like '2012-06-30 23:59:60' and can
be added randomly, with 6 months prior notice, due to the slowing of
the earths rotation
GMT con...
INSERT with SELECT
I have a query that inserts using a select:
8 Answers
8
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Generate a random number in the range 1 - 10
... 1 and 10 you mean any float that is >= 1 and < 10, then it's easy:
select random() * 9 + 1
This can be easily tested with:
# select min(i), max(i) from (
select random() * 9 + 1 as i from generate_series(1,1000000)
) q;
min | max
-----------------+------------------...