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MySQL - How to select data by string length
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select LENGTH('Ö'); results 2!! András Szepesházi's answer is the correct one!
– fubo
Oct 24 '13 at 13:59
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Finding duplicate rows in SQL Server
...abase of organizations, and there are many duplicate rows. I want to run a select statement to grab all of these and the amount of dupes, but also return the ids that are associated with each organization.
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PostgreSQL Crosstab Query
... - not fit for missing attributes
crosstab(text) with 1 input parameter:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inacti...
Multiple queries executed in java in single statement
...s wondering if it is possible to execute something like this using JDBC.
"SELECT FROM * TABLE;INSERT INTO TABLE;"
Yes it is possible. There are two ways, as far as I know. They are
By setting database connection property to allow multiple queries,
separated by a semi-colon by default.
By callin...
1052: Column 'id' in field list is ambiguous
...and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
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Iterate through options
I have a <select> element in HTML. This element represents a drop down list. I'm trying to understand how to iterate through the options in the <select> element via JQuery.
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How to change options of with jQuery?
Suppose a list of options is available, how do you update the <select> with new <option> s?
9 Answers
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What is the most efficient/elegant way to parse a flat table into a tree?
...port recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive queries in MySQL 8.0 in my presentation Recursive ...
Real life example, when to use OUTER / CROSS APPLY in SQL
...1) Top N per group queries (can be more efficient for some cardinalities)
SELECT pr.name,
pa.name
FROM sys.procedures pr
OUTER APPLY (SELECT TOP 2 *
FROM sys.parameters pa
WHERE pa.object_id = pr.object_id
ORDER BY pr.n...
How can I check whether a radio button is selected with JavaScript?
...when one of the fields is null. How can I check whether a radio button is selected?
28 Answers
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