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How can I use mySQL replace() to replace strings in multiple records?

... At a very generic level UPDATE MyTable SET StringColumn = REPLACE (StringColumn, 'SearchForThis', 'ReplaceWithThis') WHERE SomeOtherColumn LIKE '%PATTERN%' In your case you say these were escaped but since you don't specify how they were escaped, let's s...
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How to reshape data from long to wide format

... Another option if performance is a concern is to use data.table's extension of reshape2's melt & dcast functions (Reference: Efficient reshaping using data.tables) library(data.table) setDT(dat1) dcast(dat1, name ~ numbers, value.var = "value") # name 1 ...
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How to center a checkbox in a table cell?

... contains nothing but a checkbox. It is rather wide because of text in the table header row. How do I center the checkbox (with inline CSS in my HTML? (I know)) ...
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php is null or empty?

... As is shown in the following table, empty($foo) is equivalent to $foo==null and is_null($foo) has the same function of $foo===null. The table also shows some tricky values regarding the null comparison. (ϕ denotes an uninitialized variables. ) ...
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What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]

... don't do it for me. Why is the top right picture not simply SELECT * FROM TableA;? Why is the top left picture not simply SELECT * FROM TableB;? Why is the top middle picture not SELECT * FROM A INTERSECT SELECT * FROM B ? etc – onedaywhen Sep 9 '11 at 10:41 ...
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MySQL remove all whitespaces from the entire column

... To replace all spaces : UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '') To remove all tabs characters : UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\t', '' ) To remove all new line characters : UPDATE `table` SET `col_name` = REP...
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SQL error “ORA-01722: invalid number”

...er, and the string cannot be converted into a number. Without seeing your table definition, it looks like you're trying to convert the numeric sequence at the end of your values list to a number, and the spaces that delimit it are throwing this error. But based on the information you've given us, ...
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SQLite select where empty?

... It looks like you can simply do: SELECT * FROM your_table WHERE some_column IS NULL OR some_column = ''; Test case: CREATE TABLE your_table (id int, some_column varchar(10)); INSERT INTO your_table VALUES (1, NULL); INSERT INTO your_table VALUES (2, ''); INSERT INTO your_t...
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Cannot change column used in a foreign key constraint

I got this error when i was trying to alter my table. 3 Answers 3 ...
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What is the advantage to using bloom filters?

...esenting sets, such as self-balancing binary search trees, tries, hash tables, or simple arrays or linked lists of the entries. Most of these require storing at least the data items themselves, which can require anywhere from a small number of bits, for small integers, to an arbitrar...