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Retrieve the maximum length of a VARCHAR column in SQL Server
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Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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MySQL Orderby a number, Nulls last
...Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://t...
Convert INT to VARCHAR SQL
I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error:
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Removing leading zeroes from a field in a SQL statement
... VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the data as '1A'.
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Index of Currently Selected Row in DataGridView
It's that simple. How do I get the index of the currently selected Row of a DataGridView ? I don't want the Row object, I want the index (0 .. n).
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Query grants for a table in postgres
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I already found it:
SELECT grantee, privilege_type
FROM information_schema.role_table_grants
WHERE table_name='mytable'
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SQL: capitalize first letter only [duplicate]
...t only for displaying and do not need the actual data in table to change:
SELECT UPPER(LEFT(word,1))+LOWER(SUBSTRING(word,2,LEN(word))) FROM [yourtable]
Hope this helps.
EDIT: I realised about the '-' so here is my attempt to solve this problem in a function.
CREATE FUNCTION [dbo].[CapitalizeFi...
Are PDO prepared statements sufficient to prevent SQL injection?
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$pdo->query('SET NAMES gbk');
$var = "\xbf\x27 OR 1=1 /*";
$query = 'SELECT * FROM test WHERE name = ? LIMIT 1';
$stmt = $pdo->prepare($query);
$stmt->execute(array($var));
In certain circumstances, that will return more than 1 row. Let's dissect what's going on here:
Selecting a Cha...
Difference between two dates in MySQL
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SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01');
-- result: 22:00:59, the difference in HH:MM:SS format
SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00');
-- result: 79259 the differenc...
How do I list all tables in a schema in Oracle SQL?
... schema, you need to have one or more of the following system privileges:
SELECT ANY DICTIONARY
(SELECT | INSERT | UPDATE | DELETE) ANY TABLE
or the big-hammer, the DBA role.
With any of those, you can select:
SELECT DISTINCT OWNER, OBJECT_NAME
FROM DBA_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
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