sql - Postgresql pivot? Crosstab? -


i have table (which result of query) in postgres has set of rows (the result of complicated summation of data) looks following: (the column names names of each day, , value of each column double precision.)

sun   mon   tues   wed   thurs   fri
1.24   1.11   4.51   3.21    2.21    1.01

i need have data selected 1 row results below:

day   amount
sun   1.24
mon   1.11
tues  4.51
wed   3.21
thurs 2.21
fri      1.01

i'm having difficulty getting started, need change column names values , pivot result. tried experimenting crosstab i'm not entirely sure need. advice or suggestions me going in right direction appreciated.

modifying @jack douglas's first answer:

select unnest(array['sun', 'mon', 'tue', 'wed', 'thu', 'fri']) day,        unnest(array[sun, mon, tue, wed, thu, fri]) amount t;

a little less costly according 9.0 query planner:

seq scan on t (cost=0.00..11.62 rows=360 width=192)

versus

subquery scan on z (cost=0.00..12.16 rows=360 width=68) -> seq scan on t (cost=0.00..11.26 rows=360 width=192)


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