Question

我一直在寻找this tutorial和this example试图通过JSON（＆lt; 9.5）/ JSONB（* 9.5）数据查找子字符串的高效方法。

例如，我有这些数据：

CREATE TABLE public.foo
(
  row_id SERIAL PRIMARY KEY,
  data json
);

INSERT INTO foo VALUES (1,
  '{ "name": "Book the First", "author": "Bob", "text_entry": "White Cow Walked Over the Moon" } ');
INSERT INTO foo VALUES (2,
  '{ "name": "Book the Second", "author": "Charles", "text_entry": "Humptey Dumptey sat on the Moon" } ');
INSERT INTO foo VALUES (3,
  '{ "name": "Book the Third", "author": "Jim", "text_entry": "Red Fox jumped over Brown Dog" } ');

我正在寻找一种只搜索的方法＆＃34; text_entry＆＃34;并返回任何具有子串＆＃34;月亮＆＃34; （在这种情况下，它将是id = 1＆amp; 2）。预期回报：

text_entry
"White Cow Walked Over the Moon" ## has the substring "the Moon"
"Humptey Dumptey sat on the Moon" ## has the substring "the Moon"

到目前为止，我的查询看起来像这样：

    SELECT data->'text_entry'->'%the Moon%' AS query FROM foo;

ERROR:  cannot extract element from a scalar
********** Error **********

有没有优雅的方法来查询JSON / B中的子串？

Answer 1

我正在寻找一种方法来搜索“text_entry”并返回任何具有子串“月亮”的案例

SELECT data->>'text_entry' as query
FROM foo
WHERE data->>'text_entry' LIKE '%the Moon%';

- ＆GT;

query              
---------------------------------
White Cow Walked Over the Moon
Humptey Dumptey sat on the Moon
(2 rows)

对JSON数据进行子字符串搜索（错误：无法从标量中提取元素）

1 个答案: