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SQL Update with row_number()
... attempt failed primarily because you named the CTE same as the underlying table and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator.
Instead, you could just...
How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?
I am trying to dump the contents of a table to a csv file using a MySQL SELECT INTO OUTFILE statement. If I do:
13 Answers...
How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
... @blub: If you create a unique key on geb and topic it will work (ALTER TABLE table ADD UNIQUE geb_by_topic (geb, topic)).
– chaos
Aug 2 '09 at 13:43
1
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SQL - using alias in Group By
...M (
SELECT ItemName, SUBSTRING(ItemName, 1, 1) AS FirstLetter
FROM table1
) ItemNames
GROUP BY ItemName, FirstLetter
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Should I use 'border: none' or 'border: 0'?
...they behave in different ways when combined with other rules.
Borders in a table context in collapsing border model
When a table is rendered using border-collapse: collapse, then each rendered border is shared between multiple elements (inner borders are shared among as neighbor cells; outer borders...
MVC 5 Seed Users and Roles
...AppAdmin");
}
}
I used package-manager "update-database". DB and all tables were created and seeded with data.
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Can I store images in MySQL [duplicate]
...need to save as a blob, LONGBLOB datatype in mysql will work.
Ex:
CREATE TABLE 'test'.'pic' (
'idpic' INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,
'caption' VARCHAR(45) NOT NULL,
'img' LONGBLOB NOT NULL,
PRIMARY KEY ('idpic')
)
As others have said, its a bad practice but it can be don...
HTML5 LocalStorage: Checking if a key exists [duplicate]
...'s worth noting that the constraints FF (28.0) imposes on its localStorage table allows null values: CREATE TABLE webappsstore2 (scope TEXT, key TEXT, value TEXT, secure INTEGER, owner TEXT) while Chrome does not: CREATE TABLE ItemTable (key TEXT UNIQUE ON CONFLICT REPLACE, value BLOB NOT NULL ON CO...
Applying a function to every row of a table using dplyr?
...o create an appropriately vectorised function.
R provide pmax which is suitable here, however it also provides Vectorize as a wrapper for mapply to allow you to create a vectorised arbitrary version of an arbitrary function.
library(dplyr)
# use base R pmax (vectorized in C)
iris %>% mutate(max...
MySQL: @variable vs. variable. What's the difference?
...t work because my_var is not a system variable, whereas we can do set@@big_tables=1, set@@session.big_tables=1, and set session big_tables=1 because big_tables is a system variable.
– Pacerier
May 24 '15 at 23:10
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