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Select rows of a matrix that meet a condition

...20, ncol = 4) colnames(m) <- letters[1:4] The following command will select the first row of the matrix above. subset(m, m[,4] == 16) And this will select the last three. subset(m, m[,4] > 17) The result will be a matrix in both cases. If you want to use column names to select columns...
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How can I generate an INSERT script for an existing SQL Server table that includes all stored rows?

...l need to run it at the database level. Right-click the database in SSMS, select "Tasks", "Generate Scripts...". As you work through, you'll get to a "Scripting Options" section. Click on "Advanced", and in the list that pops up, where it says "Types of data to script", you've got the option to s...
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Oracle “Partition By” Keyword

...d then use that in a calculation against this records salary without a sub select, which is much faster. Read the linked AskTom article for further details. share | improve this answer | ...
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How can I resolve “Error: No developer directory found at /Developer”?

... sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer share | improve this answer | follow ...
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How to get size of mysql database?

... Run this query and you'll probably get what you're looking for: SELECT table_schema "DB Name", ROUND(SUM(data_length + index_length) / 1024 / 1024, 1) "DB Size in MB" FROM information_schema.tables GROUP BY table_schema; This query comes from the mysql forums, where there are...
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How to remove leading and trailing whitespace in a MySQL field?

...d the use case before using this solution: trim does not work while doing select query This works select replace(name , ' ','') from test; While this doesn't select trim(name) from test; share | ...
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Selecting an element in iFrame jQuery

...rame. All the elements in that loaded page have their tokenid-s. I need to select the elements by those tokenid-s. Means - I click on an element on the main page and select corresponding element in the page in the iFrame. With the help of jQuery I'm doing it in the following way: ...
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PostgreSQL: insert from another table

... Just supply literal values in the SELECT: INSERT INTO TABLE1 (id, col_1, col_2, col_3) SELECT id, 'data1', 'data2', 'data3' FROM TABLE2 WHERE col_a = 'something'; A select list can contain any value expression: But the expressions in the select list do...
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Disable dragging an image from an HTML page

... But this lead to the weird selection effect in FF atleast. Better still return false; – Bhumi Singhal Feb 22 '13 at 10:24 ...
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jQuery see if any or no checkboxes are selected

I know how to see if an individual checkbox is selected or not. 8 Answers 8 ...