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Use variable with TOP in select statement in SQL Server without making it dynamic [duplicate]
...es, in SQL Server 2005 it's possible to use a variable in the top clause.
select top (@top) * from tablename
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React JSX: selecting “selected” on selected option
In a React component for a <select> menu, I need to set the selected attribute on the option that reflects the application state.
...
Select row with most recent date per user
...
Query:
SQLFIDDLEExample
SELECT t1.*
FROM lms_attendance t1
WHERE t1.time = (SELECT MAX(t2.time)
FROM lms_attendance t2
WHERE t2.user = t1.user)
Result:
| ID | USER | TIME | IO |
---------------------------...
Row count with PDO
...
$sql = "SELECT count(*) FROM `table` WHERE foo = ?";
$result = $con->prepare($sql);
$result->execute([$bar]);
$number_of_rows = $result->fetchColumn();
Not the most elegant way to do it, plus it involves an extra query...
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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Oracle SQL: Update a table with data from another table
...his is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2
WHERE t1.id = t2.id )
Assuming the join results in a key-pr...
Using group by on multiple columns
..., to do with who is attending what subject at a university:
Table: Subject_Selection
+---------+----------+----------+
| Subject | Semester | Attendee |
+---------+----------+----------+
| ITB001 | 1 | John |
| ITB001 | 1 | Bob |
| ITB001 | 1 | Mickey |
| ITB001 ...
Regex select all text between tags
What is the best way to select all the text between 2 tags - ex: the text between all the 'pre' tags on the page.
17 Answe...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
Find a value anywhere in a database
...OT NULL
BEGIN
SET @ColumnName = ''
SET @TableName =
(
SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) &...