sql - Select column name and value from table -

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if have following table in postgresql database:

col1    col2    col3                  1        b       b       2

is there way column name each value without explicitly specifying column names? i.e. have result set like:

col1    col1    b col2    col2    b col3    1 col3    2

of course, write pl/pgsql function , query catalog table pg_attribute yourself. it's easier 1 of following:

json

the function row_to_json() provides functionality goes half way. introduced postgres 9.2:

select row_to_json(t, true) tbl t;

you don't have mention column names @ all, function derives them table type.

->sqlfiddle demo.

but you'll need json_each_text() postgres 9.3 go way:

select json_each_text(row_to_json(t)) tbl t;

to sort order display:

select (json_each_text(row_to_json(t))).*   tbl t order  1, 2;

(it's unclear how want sort exactly.)
untested. sqlfiddle not provide postgres 9.3, yet.

hstore

however, can same additional module hstore. available since 8.4. install once with:

create extension hstore;

details:
key value pair in postgresql

query:

select (each(hstore(t))).*   tbl t order  1,2;

that's all.
again, no sqlfiddle, since 1 can't install additional modules there.


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