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Re: Continuous NULL value in a column
Posted by: Peter Brawley
Date: March 30, 2017 11:16PM

Apparently you mean not continuous (table columns are obviously discrete) but rather consecutive Nulls found when the table is ordered on a certain column.

Counting runs of consecutive values is most easily done by sucking relevant rows into a buffer using a language that has a MySQL API, eg PHP, and counting runs in the buffer.

SQL isn't so good for row-to-row logic. It can be done with SQL, but awkwardly, using user variables: set a @len value to 0, as you process each Null value, increment @len; when a non-null value occurs, reset @len, &c.

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Re: Continuous NULL value in a column
March 30, 2017 11:16PM


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