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MySQL JOIN the most recent row only?
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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
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How to show disable HTML select option in by default?
... a drop-down menu from the mysql table and hard-coded too. I have multiple select in my page, One of them is
11 Answers
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MySQL case insensitive select
Can anyone tell me if a MySQL SELECT query is case sensitive or case insensitive by default? And if not, what query would I have to send so that I can do something like:
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How to get multiple selected values of select box in php?
I have a html form which has a select list box from which you can select multiple values because its multiple property is set to multiple. Consider form method is 'GET'. The html code for the form is as follows:
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
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Try the Database Object Size Functions. An example:
SELECT pg_size_pretty(pg_total_relation_size('"<schema>"."<table>"'));
For all tables, something along the lines of:
SELECT
table_schema || '.' || table_name AS table_full_name,
pg_size_pretty(pg_total_...
How do you check what version of SQL Server for a database using TSQL?
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Try
SELECT @@VERSION
or for SQL Server 2000 and above the following is easier to parse :)
SELECT SERVERPROPERTY('productversion')
, SERVERPROPERTY('productlevel')
, SERVERPROPERTY('edition')
From: http://support....
How to get Time from DateTime format in SQL?
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SQL Server 2008:
SELECT cast(AttDate as time) [time]
FROM yourtable
Earlier versions:
SELECT convert(char(5), AttDate, 108) [time]
FROM yourtable
share
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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
I've heard that SELECT * is generally bad practice to use when writing SQL commands because it is more efficient to SELECT columns you specifically need.
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How to delete from select in MySQL?
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SELECT (sub)queries return result sets. So you need to use IN, not = in your WHERE clause.
Additionally, as shown in this answer you cannot modify the same table from a subquery within the same query. However, you can either...
Case in Select Statement
I have an SQL statement that has a CASE from SELECT and I just can't get it right. Can you guys show me an example of CASE where the cases are the conditions and the results are from the cases. For example:
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