Question

在下面的查询中，$ isComplete和$ isValid以字符串形式返回。但是，它们保存为布尔值。如何获取要返回的这些字段的布尔表示？

query =
    "SELECT
        data #>> '{id}' AS id,
        data #>> '{name}' AS name,
        data #>> '{curator}' AS curator,
        data #>  '{$isValid}' as \"$isValid\",
        data #>  '{customer}' as customer,
        data #>  '{$createdTS}' as \"$createdTS\",
        data #>  '{$updatedTS}' as \"$updatedTS\",
        data #>  '{$isComplete}' as \"$isComplete\",
        (count(keys))::numeric as \"numProducts\"
    FROM
      appointment_intakes,
      LATERAL jsonb_object_keys(data #> '{products}') keys
    GROUP BY id"

Answer 1

简单地将文本转换为布尔值：

create table jsonb_test (id int, data jsonb);
insert into jsonb_test values
(1, '{"is_boolean" : true}'),
(2, '{"is_boolean" : false}');

select id, data, (data->>'is_boolean')::boolean as is_boolean
from jsonb_test
where (data->>'is_boolean')::boolean

 id |          data          | is_boolean 
----+------------------------+------------
  1 | {"is_boolean": true}   | t
(1 row)

请注意，您还可以将其他json文本值转换为boolean，例如：

insert into jsonb_test values
(3, '{"is_boolean" : "true"}'),
(4, '{"is_boolean" : "false"}'),
(5, '{"is_boolean" : "t"}'),
(6, '{"is_boolean" : "f"}'),
(7, '{"is_boolean" : "on"}'),
(8, '{"is_boolean" : "off"}');

select id, data, (data->>'is_boolean')::boolean as is_boolean
from jsonb_test
where (data->>'is_boolean')::boolean

 id |          data          | is_boolean 
----+------------------------+------------
  1 | {"is_boolean": true}   | t
  3 | {"is_boolean": "true"} | t
  5 | {"is_boolean": "t"}    | t
  7 | {"is_boolean": "on"}   | t
(4 rows)

阅读布尔类型in the documentation.

的有效文字

更新

Postgres 11 将JSONB标量的强制转换添加到数字和布尔数据类型。此查询仅适用于常规布尔JSONB标量（即true或false）：

select id, data, (data->'is_boolean')::boolean as is_boolean
from jsonb_test
where (data->'is_boolean')::boolean

在postgresql中，如何在jsonb键上返回布尔值而不是字符串？

1 个答案: