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An explicit value for the identity column in table can only be specified when a column list is used
...tead of
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table
SELECT *
FROM source_table;
SET IDENTITY_INSERT archive_table OFF;
you need to write
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table (field1, field2, ...)
SELECT field1, field2, ...
FROM source_table;...
What's the $unwind operator in MongoDB?
...oDB employs an "NoSQL" approach to data storage, so perish the thoughts of selects, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being sai...
I need to store postal codes in a database. How big should the column be?
...nce a block on one side of the street. To find a broader region, you would select the first half of the postal code. Having this information in a separate table really won't help anything and would be more complicated to maintain.
– RevNoah
Dec 2 '13 at 17:08
...
Generate MD5 hash string with T-SQL
...
Use HashBytes
SELECT HashBytes('MD5', 'email@dot.com')
That will give you 0xF53BD08920E5D25809DF2563EF9C52B6
-
SELECT CONVERT(NVARCHAR(32),HashBytes('MD5', 'email@dot.com'),2)
That will give you F53BD08920E5D25809DF2563EF9C52B6
...
SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
Which is faster: multiple single INSERTs or one multiple-row INSERT?
I am trying to optimize one part of my code that inserts data into MySQL. Should I chain INSERTs to make one huge multiple-row INSERT or are multiple separate INSERTs faster?
...
Where to place the 'assets' folder in Android Studio?
...
Select the app folder and then:
File > New > folder > assets Folder ,
the default location is inside /main folder
share
|
...
MySQL Cannot Add Foreign Key Constraint
...
lol same. MySQL could use more precise error handling on this kind of stuff.
– dave
Apr 17 at 23:38
add a comm...
What would be a good docker webdev workflow?
... persistance indepent of your CMS container, you can use one container for MySQL and one container for your CMS. In such case, you can have your MySQL container still running and your can redeploy your CMS as often as you want independently.
For development - the another option is to map mysql data ...
Set value to NULL in MySQL
...
You're probably quoting 'NULL'. NULL is a reserved word in MySQL, and can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
...