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jQuery remove options from select
I have a page with 5 selects that all have a class name 'ct'. I need to remove the option with a value of 'X' from each select while running an onclick event. My code is:
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How to check if a table exists in a given schema
... whether a table (or view) exists, and the current user has access to it?
SELECT EXISTS (
SELECT FROM information_schema.tables
WHERE table_schema = 'schema_name'
AND table_name = 'table_name'
);
The information schema is mainly useful to stay portable across major versions and...
SQL injection that gets around mysql_real_escape_string()
...ollowing query:
$iId = mysql_real_escape_string("1 OR 1=1");
$sSql = "SELECT * FROM table WHERE id = $iId";
mysql_real_escape_string() will not protect you against this.
The fact that you use single quotes (' ') around your variables inside your query is what protects you against this. The fo...
How do you create a read-only user in PostgreSQL?
I'd like to create a user in PostgreSQL that can only do SELECTs from a particular database. In MySQL the command would be:
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Join vs. sub-query
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@JinghuiNiu Customers who bought expensive items: select custid from cust join bought using (custid) where price > 500. If a customer bought multiple expensive items, you'll get double-ups. To fix this, select custid from cust where exists (select * from bought where cust...
SELECT * WHERE NOT EXISTS
...uming these tables should be joined on employeeID, use the following:
SELECT *
FROM employees e
WHERE NOT EXISTS
(
SELECT null
FROM eotm_dyn d
WHERE d.employeeID = e.id
)
You can join these tables with a LEFT JOIN keyword and filter out the...
Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
How can I remove the gloss on a select element in Safari on Mac?
On Macs and iOS devices, in Safari, a <select> element with a background color generates a gloss over itself. This does not seem to happen in other operating systems.
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How to see the values of a table variable at debug time in T-SQL?
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DECLARE @v XML = (SELECT * FROM <tablename> FOR XML AUTO)
Insert the above statement at the point where you want to view the table's contents. The table's contents will be rendered as XML in the locals window, or you can add @v to the...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...