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SQL NVARCHAR and VARCHAR Limits
... large (unavoidable) dynamic SQL query. Due to the number of fields in the selection criteria the string containing the dynamic SQL is growing over 4000 chars. Now, I understand that there is a 4000 max set for NVARCHAR(MAX) , but looking at the executed SQL in Server Profiler for the statement
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Why does Oracle 9i treat an empty string as NULL?
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@sehe the confusing bit for me is select 1 from dual where ('' is null)
– matt freake
Aug 22 '13 at 15:58
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Query to list number of records in each table in a database
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If you're using SQL Server 2005 and up, you can also use this:
SELECT
t.NAME AS TableName,
i.name as indexName,
p.[Rows],
sum(a.total_pages) as TotalPages,
sum(a.used_pages) as UsedPages,
sum(a.data_pages) as DataPages,
(sum(a.total_pages) * 8) / 1024 as To...
How to create a new database after initally installing oracle database 11g Express Edition?
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In the Connections pane, click the icon New Connection.
The New/Select Database Connection window opens.
In the New/Select Database Connection window, type the appropriate
values in the fields Connection Name, Username, and Password.
For security, the password characters that ...
How can I find non-ASCII characters in MySQL?
...ng as "ASCII", but I would suggest trying a variant of a query like this:
SELECT * FROM tableName WHERE columnToCheck NOT REGEXP '[A-Za-z0-9]';
That query will return all rows where columnToCheck contains any non-alphanumeric characters. If you have other characters that are acceptable, add them ...
How do I set the size of Emacs' window?
... got the following in my .emacs:
(if (window-system)
(set-frame-height (selected-frame) 60))
You might also look at the functions set-frame-size, set-frame-position, and set-frame-width. Use C-h f (aka M-x describe-function) to bring up detailed documentation.
I'm not sure if there's a way to ...
Sanitizing strings to make them URL and filename safe?
...OU
echo normal_chars('üÿÄËÏÖÜŸåÅ'); // uyAEIOUYaA
Based on the selected answer in this thread: URL Friendly Username in PHP?
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Generate list of all possible permutations of a string
...re x and y is how you define them and r is the number of characters we are selecting from --if I am understanding you correctly. You should definitely generate these as needed and not get sloppy and say, generate a powerset and then filter the length of strings.
The following definitely isn't the b...
SELECT DISTINCT on one column
...ou're on SQL Server 2005 or greater, you can use a CTE with ROW_NUMBER():
SELECT *
FROM (SELECT ID, SKU, Product,
ROW_NUMBER() OVER (PARTITION BY PRODUCT ORDER BY ID) AS RowNumber
FROM MyTable
WHERE SKU LIKE 'FOO%') AS a
WHERE a.RowNumber = 1
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ROW_NUMBER() in MySQL
...asy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.col1 AND t0.col2=t1.col2 AND t1.col3>t0.col3
WHERE t1.col1 IS NULL;
“Get the rows in the table for which no other row with matching col1,col2 has a hi...