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Tag: postgresql

Aggregate functions across multiple columns in postgres

I have a postgresql table with multiple fields containing integers (a1,a2,a3 etc). I want to run aggregate functions(mean, standard deviation etc) across more than one of the columns at once. (Some of them may have a reasonable number of nulls, so I don’t want to just generate column averages and then average those). I can get a set of integers

PostgreSQL – Query Optimization

I have this below query which takes about 15-20 secs to run. with cte0 as ( SELECT label, date, CASE WHEN Lead(label || date || “number”) OVER (PARTITION BY label || date || “number” ORDER BY “label”, “date”, “number”, “time”) IS NULL THEN ‘1’::numeric ELSE ‘0’::numeric END As “unique” FROM table_data LEFT JOIN table_mapper ON table_mapper.”type” = table_data.”type” WHERE Date

Why isn’t SQLAlchemy creating serial columns?

SQLAlchemy is generating, but not enabling, sequences for columns in postgresql. I suspect I may be doing something wrong in engine setup. Using an example from the SQLAlchemy tutorial (http://docs.sqlalchemy.org/en/rel_0_9/orm/tutorial.html): With this script, the following table is generated: However, a sequence was created: SQLAlchemy 0.9.1, Python 2.7.5+, Postgresql 9.3.1, Ubuntu 13.10 -Reece Answer this is because you provided it with