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UITableView Setting some cells as “unselectable”
How can I set the UITableView's cell property to be unselectable? I don't want to see that blue selection box when the user taps on the cell.
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Get record counts for all tables in MySQL database
...get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
19 Answers
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Rails select helper - Default selected value, how?
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This should do it:
<%= f.select :project_id, @project_select, :selected => params[:pid] %>
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How can I list ALL grants a user received?
...ust direct table grants (e.g., grants via roles, system privileges such as select any table, etc.), here are some additional queries:
System privileges for a user:
SELECT PRIVILEGE
FROM sys.dba_sys_privs
WHERE grantee = <theUser>
UNION
SELECT PRIVILEGE
FROM dba_role_privs rp JOIN role_...
PostgreSQL DISTINCT ON with different ORDER BY
...llowing approaches:
The general solution that should work in most DBMSs:
SELECT t1.* FROM purchases t1
JOIN (
SELECT address_id, max(purchased_at) max_purchased_at
FROM purchases
WHERE product_id = 1
GROUP BY address_id
) t2
ON t1.address_id = t2.address_id AND t1.purchased_at = t2...
How to get a date in YYYY-MM-DD format from a TSQL datetime field?
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SELECT CONVERT(char(10), GetDate(),126)
Limiting the size of the varchar chops of the hour portion that you don't want.
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How do I use ROW_NUMBER()?
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For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Ro...
What is the reason not to use select *?
...eople claim that you should specifically name each column you want in your select query.
20 Answers
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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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Rails: select unique values from a column
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Model.select(:rating)
Result of this is a collection of Model objects. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (mo...