How to access a RowDataPacket object

Question

I m currently developing a desktop application with Node-webkit  During that process I need to get some data from a local MySQL-database   The querying works fine  but I can t figure out how to access the results  I store all of them in an array that is then passed to a function  In the console they look like this   RowDataPacket  user id  101  ActionsPerformed  20  RowDataPacket  user id  102  ActionsPerformed  110  RowDataPacket  user id  104  ActionsPerformed  3    And here is the query structure   var ret       conn query SQLquery  function err  rows  fields        if  err          alert             else           for  var i of rows               ret push i             doStuffwithTheResult ret       How do I retrieve this in the doStuffwithTheResult function  The values are more important  but if I could get the keys as well that would be great

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I also met the same problem recently  when I use waterline in express project for complex queries  use the SQL statement to query   this is my solution  first transform the return value RowDataPacket object  into  string  and then convert this string into the json object   The following is code      select all user          find  function req  res  next       console log  i am in user find list        var sql  select   from tb user        req models tb user query sql function err  results            console log   gt  gt  results     results            var string JSON stringify results           console log   gt  gt  string     string            var json    JSON parse string           console log   gt  gt  json     json           console log   gt  gt  user name     json 0  name           req list   json          next                The following is console        gt  gt  results     RowDataPacket       user id   2fc48bd0-a62c-11e5-9a32-a31e4e4cd6a5       name   wuwanyu       psw   123       school   Northeastern university                                                                                                                                                  major   Communication engineering                                                                                                                                                   points   10       datems   1450514441486       createdAt  Sat Dec 19 2015 16 42 31 GMT 0800                                                                                                                 updatedAt  Sat Dec 19 2015 16 42 31 GMT 0800                                                                                                                 ID  3      phone  2147483647      gt  gt  string      user id   2fc48bd0-a62c-11e5-9a32-a31e4e4cd6a5   name   wuwanyu   psw   123   school   Northeastern university   major   Communication engineering   points   10   datems   1450514 441486   createdAt   2015-12-19T08 42 31 000Z   updatedAt   2015-12-19T08 42 31 000Z   ID  3  phone  2147483647    gt  gt  json       user id   2fc48bd0-a62c-11e5-9a32-a31e4e4cd6a5       name   wuwanyu       psw   123       school   Northeastern university                                                                                                                                                  major   Communication engineering                                                                                                                                                   points   10       datems   1450514441486       createdAt   2015-12-19T08 42 31 000Z       updatedAt   2015-12-19T08 42 31 000Z       ID  3      phone  2147483647      gt  gt  user name   wuwanyu

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going off of jan s answer of shallow-copying the object  another clean implementation using map function   High level of what this solution does  iterate through all the rows and copy the rows as valid js objects        function  will be used on every row returned by the query const objectifyRawPacket   row   gt       row        iterate over all items and convert the raw packet row - gt  js object const convertedResponse   results map objectifyRawPacket     We leveraged the array map function  it will go over every item in the array  use the item as input to the function  and insert the output of the function into the array you re assigning    more specifically on the objectifyRawPacket function  each time it s called its seeing the    RawDataPacket    from the source array  These objects act a lot like normal objects - the        spread  operator copies items from the array after the periods - essentially copying the items into the object it s being called in    The parens around the spread operator on the function are necessary to implicitly return an object from an arrow function

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With Object prototype approach  JSON parse JSON stringify rows   returns object  extract values with Object values   const result   Object values JSON parse JSON stringify rows      Usage  result forEach  v    gt  console log v

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Turns out they are normal objects and you can access them through user id   RowDataPacket is actually the name of the constructor function that creates an object  it would look like this  new RowDataPacket user id        You can check by accessing its name  0  constructor name  If the result is an array  you would have to use  0  user id

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Simpler way    then  resp  gt      let resultFromDb  Object values resp  0    console log resultFromDb      In my example I received an object in response   When I use Object values I have the value of the property as a response  however it comes inside an array  using  0  access the first index of this array  now i have the value to use it where I need it

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Hi try this 100  works   results JSON parse JSON stringify results   doStuffwithTheResult results

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I had this problem when trying to consume a value returned from a stored procedure   console log result 0      would output    RowDataPacket   datetime   2019-11-15 16 37 05         I found that   console log results 0  0  datetime     Gave me the value I wanted

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db query  select   from login   err  results  fields   gt       if err           console log  error in fetching data             var string JSON stringify results       console log string       var json    JSON parse string         to get one value here is the option     console log json 0  name

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If anybody needs to retrive specific RowDataPacket object from multiple queries  here it is  Before you start Important  Ensure you enable multipleStatements in your mysql connection like so     Connection to MySQL var db   mysql createConnection     host       localhost     user       root     password   123     database   TEST     multipleStatements  true      Multiple Queries Let s say we have multiple queries running       All Queries are here   const lastCheckedQuery         -- Query 1     SELECT   FROM table1            -- Query 2     SELECT   FROM table2                    Run the query   db query lastCheckedQuery   error  result    gt        if error             Show error       return res status 500  send  quot Unexpected database error quot           If we console log result  you ll get such output            RowDataPacket         id  1        ColumnFromTable1   a                      RowDataPacket         id  1        ColumnFromTable2   b                Both results show for both tables  Here is where basic Javascript array s come in place https   developer mozilla org en-US docs Web JavaScript Reference Global Objects Array To get data from table1 and column named ColumnFromTable1 we do result 0  0  ColumnFromTable1    Notice the double  0   which gives us result of a

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I really don t see what is the big deal with this I mean look if a run my sp which is CALL ps get roles     Yes I get back an ugly ass response from DB and stuff  Which is this one              RowDataPacket         id  1        role   Admin         created at   2019-12-19 16 03 46             RowDataPacket         id  2        role   Recruiter         created at   2019-12-19 16 03 46             RowDataPacket         id  3        role   Regular         created at   2019-12-19 16 03 46               OkPacket       fieldCount  0      affectedRows  0      insertId  0      serverStatus  35      warningCount  0      message          protocol41  true      changedRows  0          it is an array that kind of look like this    rows 0          RowDataPacket     them table rows          RowDataPacket          RowDataPacket         rows 1    OkPacket         them props         but if I do an http response to index  0  of rows at the client I get          id  1  role   Admin   created at   2019-12-19 16 03 46         id  2  role   Recruiter   created at   2019-12-19 16 03 46        id  3  role   Regular   created at   2019-12-19 16 03 46       and I didnt have to do none of yow things   rows 0  map row   gt       return console log  row         row          the output gets some like this   row     id  1  role   Admin   created at   2019-12-19 16 03 46    row     id  2  role   Recruiter   created at   2019-12-19 16 03 46    row     id  3  role   Regular   created at   2019-12-19 16 03 46      So you all is tripping for no reason  Or it also could be the fact that I m running store procedures instead of regular querys  the response from query and sp is not the same

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Solution Just do  JSON stringify results

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You can copy all enumerable own properties of an object to a new one by Object assign target     sources    trivial object   Object assign     non trivial object     so in your scenario  it should be enough to change  ret push i     to  ret push Object assign     i

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I found an easy way  Object prototype parseSqlResult   function          return JSON parse JSON stringify this 0        At db layer do the parsing as  let users  await util knex raw  select   from user       return users parseSqlResult     This will return elements as normal JSON array

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you try the code which gives JSON without rowdatapacket   var ret       conn query SQLquery  function err  rows  fields        if  err          alert             else           ret   JSON stringify rows             doStuffwithTheResult ret

[mysql] How to access a RowDataPacket object

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