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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...
MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
...
Rewrite the query into this
SELECT st1.*, st2.relevant_field FROM sometable st1
INNER JOIN sometable st2 ON (st1.relevant_field = st2.relevant_field)
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > 1
I think st2.relevant_...
How do you display code snippets in MS Word preserving format and syntax highlighting?
...d install Notepad++ and do the following:
Paste your code in the window;
Select the programming language from the language menu;
Select the text to copy;
Right click and select Plugin commands -> Copy Text with Syntax Highlighting;
Paste it into MS Word and you are good to go!
Update 29/06/20...
Xcode duplicate line
... command item as the screenshot below (name them what you want):
That's: selectLine:, copy:, moveToEndOfLine:, insertNewline:, paste:, deleteBackward:
Restart Xcode and go to Preferences - Key Bindings, search for your command.
Set a key combination for the command:
Finally unleashed the power of...
Xcode + remove all breakpoints
...l breakpoints.
In Xcode4 press CMD(⌘)+6, in Xcode3 press CMD(⌘)+ALT+B.
Select all breakpoints with CMD(⌘)+A and delete them, like deleting text, with backspace.
There's no step 3 :)
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The multi-part identifier could not be bound
...tion is specified in the WHERE clause).
Here's an outline of your query:
SELECT
…
FROM a, b LEFT JOIN dkcd ON …
WHERE …
You are probably expecting it to behave like this:
SELECT
…
FROM (a, b) LEFT JOIN dkcd ON …
WHERE …
that is, the combination of tables a and b is joined with...
Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...
How to reset sequence in postgres and fill id column with new data?
...
SELECT setval('seq', 1, FALSE) should do the same (here, the third argument, FALSE, does the magic, as it shows that nextval must be 1 instead of 2)
– Vasilen Donchev
Sep 22 '15 at 14:43...
How to remove a web site from google analytics
...e awhile to figure out.
Go to the Admin tab.
In the middle column, select the web property that you want to delete from the dropdown.
In the right-hand column, click on "View Settings." ("Property Settings" in dec. 2015)
At the bottom of the next page, select "Delete this view."
...
How do I escape a reserved word in Oracle?
In TSQL I could use something like Select [table] from tablename to select a column named "table".
5 Answers
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