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PreparedStatement IN clause alternatives?
... and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful.
Prepare SELECT my_column FROM my_table WHERE search_...
MySQL order by before group by
... table on both the post_author and the max date.
The solution should be:
SELECT p1.*
FROM wp_posts p1
INNER JOIN
(
SELECT max(post_date) MaxPostDate, post_author
FROM wp_posts
WHERE post_status='publish'
AND post_type='post'
GROUP BY post_author
) p2
ON p1.post_author = p...
How to get a date in YYYY-MM-DD format from a TSQL datetime field?
...
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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MySQL “Group By” and “Order By”
I want to be able to select a bunch of rows from a table of e-mails and group them by the from sender. My query looks like this:
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Using DISTINCT and COUNT together in a MySQL Query
...
use
SELECT COUNT(DISTINCT productId) from table_name WHERE keyword='$keyword'
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Find the number of columns in a table
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SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_catalog = 'database_name' -- the database
AND table_name = 'table_name'
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this.setState isn't merging states as I would expect
...do recursive merge.
You can use the value of the current state this.state.selected to construct a new state and then call setState() on that:
var newSelected = _.extend({}, this.state.selected);
newSelected.name = 'Barfoo';
this.setState({ selected: newSelected });
I've used function _.extend() ...
SQL Server query - Selecting COUNT(*) with DISTINCT
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Count all the DISTINCT program names by program type and push number
SELECT COUNT(DISTINCT program_name) AS Count,
program_type AS [Type]
FROM cm_production
WHERE push_number=@push_number
GROUP BY program_type
DISTINCT COUNT(*) will return a row for each unique count. What you want is C...
What is the difference between HAVING and WHERE in SQL?
What is the difference between HAVING and WHERE in an SQL SELECT statement?
20 Answers
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Selecting only numeric columns from a data frame
...traightforward, and robust to use on database-back-ended tibbles:
dplyr::select_if(x, is.numeric)
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