这可能是一个很好的起点(仅限8.4+版本):

SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field

array_agg返回一个数组，但是可以将其CAST为文本并根据需要进行编辑(参见下面的说明)。

在8.4版本之前，你必须在使用之前自己定义:

CREATE AGGREGATE array_agg (anyelement)
(
    sfunc = array_append,
    stype = anyarray,
    initcond = '{}'
);

(转述自PostgreSQL文档)

澄清:

The result of casting an array to text is that the resulting string starts and ends with curly braces. Those braces need to be removed by some method, if they are not desired. Casting ANYARRAY to TEXT best simulates CSV output as elements that contain embedded commas are double-quoted in the output in standard CSV style. Neither array_to_string() or string_agg() (the "group_concat" function added in 9.1) quote strings with embedded commas, resulting in an incorrect number of elements in the resulting list. The new 9.1 string_agg() function does NOT cast the inner results to TEXT first. So "string_agg(value_field)" would generate an error if value_field is an integer. "string_agg(value_field::text)" would be required. The array_agg() method requires only one cast after the aggregation (rather than a cast per value).

SELECT array_to_string(array(SELECT a FROM b),', ');

也行。

这可能是一个很好的起点(仅限8.4+版本):

SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field

array_agg返回一个数组，但是可以将其CAST为文本并根据需要进行编辑(参见下面的说明)。

在8.4版本之前，你必须在使用之前自己定义:

CREATE AGGREGATE array_agg (anyelement)
(
    sfunc = array_append,
    stype = anyarray,
    initcond = '{}'
);

(转述自PostgreSQL文档)

澄清:

The result of casting an array to text is that the resulting string starts and ends with curly braces. Those braces need to be removed by some method, if they are not desired. Casting ANYARRAY to TEXT best simulates CSV output as elements that contain embedded commas are double-quoted in the output in standard CSV style. Neither array_to_string() or string_agg() (the "group_concat" function added in 9.1) quote strings with embedded commas, resulting in an incorrect number of elements in the resulting list. The new 9.1 string_agg() function does NOT cast the inner results to TEXT first. So "string_agg(value_field)" would generate an error if value_field is an integer. "string_agg(value_field::text)" would be required. The array_agg() method requires only one cast after the aggregation (rather than a cast per value).

试着这样做:

select field1, array_to_string(array_agg(field2), ',')
from table1
group by field1;

从9.0开始，这变得更容易了:

SELECT id, 
       string_agg(some_column, ',')
FROM the_table
GROUP BY id

我在postgresql中的建议

SELECT cpf || ';' || nome || ';' || telefone  
FROM (
      SELECT cpf
            ,nome
            ,STRING_AGG(CONCAT_WS( ';' , DDD_1, TELEFONE_1),';') AS telefone 
      FROM (
            SELECT DISTINCT * 
            FROM temp_bd 
            ORDER BY cpf DESC ) AS y
      GROUP BY 1,2 ) AS x