Use mysql fetch array with foreach instead of while

Question

i want to know how do we convert the following code to work with foreach   query select    SELECT   FROM shouts ORDER BY id DESC LIMIT 8           result select   mysql query  query select  or die mysql error          while  row   mysql fetch array  result select              ename   stripslashes  row  name              eemail   stripcslashes  row  email              epost   stripslashes  row  post              eid    row  id              grav url    http   www gravatar com avatar php gravatar id   md5 strtolower  eemail     amp size 70            echo    lt img src         grav url      alt  Gravatar  gt     lt br  gt              echo  eid     lt br  gt             echo  ename     lt br  gt             echo  eemail     lt br  gt             echo  epost     lt br  gt  lt br  gt  lt br  gt  lt br  gt

User · Answer

There s not a good way to convert it to foreach  because mysql fetch array   just fetches the next result from  result select   If you really wanted to foreach  you could do pull all the results into an array first  doing something like the following    result list   array    while  row   mysql fetch array  result select        result list      row     foreach  result list as  row               But there s no good reason I can see to do that - and you still have to use the while loop  which is unavoidable due to how mysql fetch array   works   Why is it so important to use a foreach     EDIT  If this is just for learning purposes  you can t convert this to a foreach   You have to have a pre-existing array to use a foreach   instead of a while    and mysql fetch array   fetches one result per call - there s no pre-existing array for foreach   to iterate through

User · Answer

You can code like this    query select    SELECT   FROM shouts ORDER BY id DESC LIMIT 8     result select   mysql query  query select  or die mysql error      rows   array    while  row   mysql fetch array  result select        rows      row  foreach  rows as  row         ename   stripslashes  row  name          eemail   stripcslashes  row  email          epost   stripslashes  row  post          eid    row  id          grav url    http   www gravatar com avatar php gravatar id   md5 strtolower  eemail     amp size 70        echo    lt img src         grav url      alt  Gravatar  gt     lt br  gt          echo  eid     lt br  gt         echo  ename     lt br  gt         echo  eemail     lt br  gt         echo  epost     lt br  gt  lt br  gt  lt br  gt  lt br  gt        As you can see  it s still need a loop while to get data from mysql fetch array

User · Answer

To use foreach would require you have an array that contains every row from the query result  Some DB libraries for PHP provide a fetch all function that provides an appropriate array but I could not find one for mysql  however the mysqli extension does    You could of course write your own  like so  function mysql fetch all  result        rows   array       while   row   mysql fetch array  result           rows      row          return  rows      However I must echo the  why   Using this function you are creating two loops instead of one  and requring the entire result set be loaded in to memory  For sufficiently large result sets  this could become a serious performance drag  And for what    foreach  mysql fetch all  result  as  row    vs  while   row   mysql fetch array  result     while is just as concise and IMO more readable   EDIT There is another option  but it is pretty absurd  You could use the Iterator Interface  class MysqlResult implements Iterator     private  rownum   0    private  numrows   0    private  result     public function   construct  result         this- gt result    result       this- gt numrows   mysql num rows  result          public function rewind          this- gt rownum   0         public function current         mysql data seek  this- gt result   this- gt rownum       return mysql fetch array  this- gt result          public function key         return  this- gt rownum         public function next          this- gt rownum           public function valid         return  this- gt rownum  lt   this- gt numrows   true   false          rows   new MysqlResult mysql query  query select     foreach   rows as  row        code        In this case  the MysqlResult instance fetches rows only on request just like with while  but wraps it in a nice foreach-able package  While you ve saved yourself a loop  you ve added the overhead of class instantiation and a boat load of function calls  not to mention a good deal of added code complexity   But you asked if it could be done without using while  or for I imagine   Well it can be done  just like that  Whether it should be done is up to you

User · Answer

You could just do it like this   query select    SELECT   FROM shouts ORDER BY id DESC LIMIT 8       result select   mysql query  query select  or die mysql error       foreach  result select as  row        ename   stripslashes  row  name          eemail   stripcslashes  row  email          epost   stripslashes  row  post          eid    row  id          grav url    http   www gravatar com avatar php gravatar id   md5 strtolower  eemail     amp size 70        echo    lt img src         grav url      alt  Gravatar  gt     lt br  gt          echo  eid     lt br  gt         echo  ename     lt br  gt         echo  eemail     lt br  gt         echo  epost     lt br  gt  lt br  gt  lt br  gt  lt br  gt

User · Answer

the most obvious way to make foreach a possibility includes materializing the whole resultset in an array  which will probably kill you memory-wise  sooner or later   you d need to turn to iterators to avoid that problem   see http   www php net  helly php ext spl

[php] Use mysql_fetch_array() with foreach() instead of while()

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