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Maximum number of records in a MySQL database table
...g with multiple billions of entries? (which would probably just make your select statements melt down long before then)
– Kzqai
Apr 26 '10 at 19:35
2
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Unknown column in 'field list' error on MySQL Update query
..._user_profile.fellow = 'y'
WHERE
master_user_profile.user_id IN (
SELECT tran_user_branch.user_id
FROM tran_user_branch WHERE tran_user_branch.branch_id = 17);
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SQL UPDATE all values in a field with appended string CONCAT not working
...
That's pretty much all you need:
mysql> select * from t;
+------+-------+
| id | data |
+------+-------+
| 1 | max |
| 2 | linda |
| 3 | sam |
| 4 | henry |
+------+-------+
4 rows in set (0.02 sec)
mysql> update t set data=concat(data, 'a');...
Difference between partition key, composite key and clustering key in Cassandra?
...KEY:
insert into stackoverflow_simple (key, data) VALUES ('han', 'solo');
select * from stackoverflow_simple where key='han';
table content
key | data
----+------
han | solo
COMPOSITE/COMPOUND KEY can retrieve "wide rows" (i.e. you can query by just the partition key, even if you have clusteri...
Emacs bulk indent for Python
...
I use the following snippet. On tab when the selection is inactive, it indents the current line (as it normally does); when the selection is inactive, it indents the whole region to the right.
(defun my-python-tab-command (&optional _)
"If the region is active, s...
How to add “on delete cascade” constraints?
...hy until you see "Constraints"), or you can query the information schema.
select *
from information_schema.key_column_usage
where position_in_unique_constraint is not null
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Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
How do I copy items from list to list without foreach?
...single property to another list is needed:
targetList.AddRange(sourceList.Select(i => i.NeededProperty));
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How to change Android version and code version number?
...Ctrl+Alt+Shift+S in android studio or go to File > Project Structure...
Select app on left side and select falvors tab on right side on default config change version code , name and etc...
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LIKE vs CONTAINS on SQL Server
...o will always require a full table scan.
The CONTAINS query should be:
SELECT * FROM table WHERE CONTAINS(Column, 'test');
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