Question

我试图通过查询在我的JSON中获取一个元素。

我正在使用Groovy，Postgres 9.4和JSONB。

这是我的JSON

UIFont *postFont = [UIFont fontWithName:@"OpenSans" size:13.0];

NSString *postWithFont = [self.msgHtml stringByAppendingString:[NSString stringWithFormat:@"<style>body{font-family: '%@'; font-size:%fpx;}i{font-family: '%@'; font-size:%fpx;}</style>", postFont.fontName, postFont.pointSize, [postFont.fontName stringByAppendingString:@"-Italic"], postFont.pointSize]];

_mainText = [[NSMutableAttributedString alloc]
                                       initWithData:[postWithFont dataUsingEncoding:NSUTF8StringEncoding]
                                       options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType,
                                                 NSCharacterEncodingDocumentAttribute: @(NSUTF8StringEncoding)}
                                       documentAttributes:nil
                                       error:nil];

我想通过ID获取系列数组中的各个元素，我目前正在使用此查询

{
    "id": "${ID}",
    "team": {
        "id": "123",
        "name": "Shire Soldiers"
    },
    "playersContainer": {
        "series": [
            {
                "id": "1",
                "name": "Nick",
                "teamName": "Shire Soldiers",
                "ratings": [
                    1,
                    5,
                    6,
                    9
                ],
                "assists": 17,
                "manOfTheMatches": 20,
                "cleanSheets": 1,
                "data": [
                    3,
                    2,
                    3,
                    5,
                    6
                ],
                "totalGoals": 19

            },

            {

                "id": "2",
                "name": "Pasty",
                "teamName": "Shire Soldiers",
                "ratings": [
                    6,
                    8,
                    9,
                    10
                ],
                "assists": 25,
                "manOfTheMatches": 32,
                "cleanSheets": 2,
                "data": [
                    3,
                    5,
                    7,
                    9,
                    10
                ],
                "totalGoals": 24

            }
        ]
    }
}

然而，这让我回到了id为1和2的元素

以下是我的回复

select content->'playersContainer'->'series' from site_content 
where content->'playersContainer'->'series' @> '[{"id":"1"}]';

谁能看到我哪里出错了？我在这里看到了其他一些问题，但他们对此没有帮助。

Answer 1

content->'playersContainer'->'series'是一个数组。如果要在数组中查找特定元素，请使用jsonb_array_elements()。

select elem
from site_content,
lateral jsonb_array_elements(content->'playersContainer'->'series') elem
where elem @> '{"id":"1"}';

Test it here.

使用Postgres查询JSONB

1 个答案: