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MySQL: selecting rows where a column is null
...for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows.
...
How do I limit the number of rows returned by an Oracle query after ordering?
...).
To answer the original question, here's the query:
SELECT *
FROM sometable
ORDER BY name
OFFSET 20 ROWS FETCH NEXT 10 ROWS ONLY;
(For earlier Oracle versions, please refer to other answers in this question)
Examples:
Following examples were quoted from linked page, in the hope of preventing ...
How to do a case sensitive search in WHERE clause (I'm using SQL Server)?
... Simply do the following to return all upper case 'D's. "SELECT * FROM SomeTable WHERE ColumnName like '%D%' COLLATE SQL_Latin1_General_CP1_CS_AS"
– Radderz
Dec 12 '16 at 12:19
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Why all the Active Record hate? [closed]
...problem that I see with Active Records is, that it's always just about one table
Code:
class Person
belongs_to :company
end
people = Person.find(:all, :include => :company )
This generates SQL with LEFT JOIN companies on companies.id = person.company_id, and automatically generates assoc...
Search text in stored procedure in SQL Server
... ORDER BY
ROUTINE_NAME
END
--TO FIND STRING IN ALL TABLES OF DATABASE.
BEGIN
SELECT t.name AS Table_Name
,c.name AS COLUMN_NAME
FROM sys.tables AS t
INNER JOIN sys.columns c
ON t.OBJECT_ID ...
Using a .php file to generate a MySQL dump
... or less are auto-explicative:
$dumpSettingsDefault = array(
'include-tables' => array(),
'exclude-tables' => array(),
'compress' => 'None',
'no-data' => false,
'add-drop-database' => false,
'add-drop-table' => false,
'single-transaction' => true,
...
Using OR in SQLAlchemy
...
This has been really helpful.
Here is my implementation for any given table:
def sql_replace(self, tableobject, dictargs):
#missing check of table object is valid
primarykeys = [key.name for key in inspect(tableobject).primary_key]
filterargs = []
for primkeys in primarykeys:...
Multiple INSERT statements vs. single INSERT with multiple VALUES
...irely of duplicate rows and neither affects the order of the output of the table of the constants (and as you are inserting into a heap time spent sorting would be pointless anyway even if it did).
Moreover if a clustered index is added to the table the plan still shows an explicit sort step so it...
Filter data.frame rows by a logical condition
...
we can use data.table library
library(data.table)
expr <- data.table(expr)
expr[cell_type == "hesc"]
expr[cell_type %in% c("hesc","fibroblast")]
or filter using %like% operator for pattern matching
expr[cell_type %like% "hesc...
How do you version your database schema? [closed]
... sure that schema changes are always additive. So I don't drop columns and tables, because that would zap the data and cannot be rolled back later. This way the code that uses the database can be rolled back without losing data or functionality.
I have a migration script that contains statements th...