如何在postgres中解析文本列的json值

Question

I have a column of text type be contain json value.

{"summary":"this is a example","url":"stackoverflow.com"}

How can I extract ' url ' json field of column in postgres with query?

I used of following query:

 SELECT jvalue->>'url' From table;

With my query, I get following error.

SQL Error [42883]: ERROR: operator does not exist: text ->> unknown Hint: No operator matches the given name and argument type(s). You might need to add explicit type casts. org.postgresql.util.PSQLException: ERROR: operator does not exist: text ->> unknown Hint: No operator matches the given name and argument type(s). You might need to add explicit type casts.

Answer 1

您可以使用->运算符：

SELECT '{"summary":"this is a example","url":"stackoverflow.com"}'::json->'url';