java - How to read JSON data type in mysql using JDBC -


mysql 5.7 introduced json data type offers tonnes of query functions.

since there isn't compatible resultset function, how , use retrieve data stored in datatype.

it should rs.getstring, because getstring used varchar, text, can consider json string type, can result, using getstring.

simple example

double check mysql 5.7 , postgresql 9.4 :

mysql 5.7 sql

create database db_test; create table table_test(json json); insert table_test values('{"key1": "value1", "key2": "value2"}');

code

public static void checkjson() {     try {         class.forname(driver);         connection connection = drivermanager.getconnection(db_url, db_username, db_password);         string q = "select * table_test";         preparedstatement preparedstatement = connection.preparestatement(q);         preparedstatement.execute();         resultset rs = preparedstatement.executequery();         while (rs.next()) {             system.out.println(rs.getstring("json"));         }      } catch (classnotfoundexception | sqlexception e) {         e.printstacktrace();     } }

it print me :

{"key1": "value1", "key2": "value2"}

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