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'Incomplete final line' warning when trying to read a .csv file into R
...here's no way that in your case the warning was thrown by the function readTableHeader, because that one doesn't read the final line. Hence your problem is not the same as that of the OP.
– Joris Meys
May 1 at 11:31
...
Can I protect against SQL injection by escaping single-quote and surrounding user input with single-
...rmissions in the database to executing the needed SPs only, and not access tables directly.
you can also easily verify that the entire codebase only accesses the DB through SPs...
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The conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value
...n using Entity Framework. This occurs when the entity associated with the table being saved has a mandatory datetime field and you do not set it with some value.
The default datetime object is created with a value of 01/01/1000 and will be used in place of null. This will be sent to the datetime ...
PostgreSQL “DESCRIBE TABLE”
How do you perform the equivalent of Oracle's DESCRIBE TABLE in PostgreSQL (using the psql command)?
22 Answers
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Length of a JavaScript object
... implemented method, but you can check which browser supports it with this table.
– aeosynth
Jun 6 '11 at 19:08
51
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What's the Hi/Lo algorithm?
...re out the next identifier value knowing we use hilo in this particular DB table?
– Vlad Mihalcea
Feb 7 '17 at 1:46
My...
MySQL error 1449: The user specified as a definer does not exist
... ALTER statements
SELECT CONCAT("ALTER DEFINER=`youruser`@`host` VIEW ",
table_name, " AS ", view_definition, ";")
FROM information_schema.views
WHERE table_schema='your-database-name';
Copy and run the ALTER statements
How to change the definer for stored procedures
Example:
UPDATE `mysql`...
How do you list all triggers in a MySQL database?
...ll triggers is:
show triggers;
or you can access the INFORMATION_SCHEMA table directly by:
select trigger_schema, trigger_name, action_statement
from information_schema.triggers
You can do this from version 5.0.10 onwards.
More information about the TRIGGERS table is here.
...
Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...ent and SQLC_CALC_FOUND_ROWS was much faster than two queries. Now my main table is only 65k and two joins of a few hundreds, but the main query takes 0.18 seconds with or without SQLC_CALC_FOUND_ROWS but when I ran a second query with COUNT(id) it took 0.25 alone.
– transilvla...
SQL query to group by day
...
If you're using SQL Server, you could add three calculated fields to your table:
Sales (saleID INT, amount INT, created DATETIME)
ALTER TABLE dbo.Sales
ADD SaleYear AS YEAR(Created) PERSISTED
ALTER TABLE dbo.Sales
ADD SaleMonth AS MONTH(Created) PERSISTED
ALTER TABLE dbo.Sales
ADD SaleDay A...