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Multiple columns index when using the declarative ORM extension of sqlalchemy
According to the documentation and the comments in the sqlalchemy.Column class, we should use the class sqlalchemy.schema.Index to specify an index that contains multiple columns.
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SQL “select where not in subquery” returns no results
Disclaimer: I have figured out the problem (I think), but I wanted to add this issue to Stack Overflow since I couldn't (easily) find it anywhere. Also, someone might have a better answer than I do.
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SQL - Update multiple records in one query
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Try either multi-table update syntax
UPDATE config t1 JOIN config t2
ON t1.config_name = 'name1' AND t2.config_name = 'name2'
SET t1.config_value = 'value',
t2.config_value = 'value2';
Here is SQLFiddle demo
or conditional update
UPDATE config
SET config_value...
Check if object value exists within a Javascript array of objects and if not add a new object to arr
If I have the following array of objects:
18 Answers
18
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The JPA hashCode() / equals() dilemma
...bernate, but I'd like to discuss them JPA-implementation-neutrally (I am using EclipseLink, by the way).
20 Answers
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Compare two DataFrames and output their differences side-by-side
I am trying to highlight exactly what changed between two dataframes.
14 Answers
14
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Are class names in CSS selectors case sensitive?
I keep reading everywhere that CSS is not case sensitive, but I have this selector
4 Answers
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How to include layout inside layout?
How to include layout inside layout in Android?
6 Answers
6
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When should I use cross apply over inner join?
What is the main purpose of using CROSS APPLY ?
13 Answers
13
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MySQL ON vs USING?
In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...