Databases
StackOverflow2013
Postsdbo
POasync + recursive + database-update operation with nodejs
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POasync + recursive + database-update operation with nodejs
    primarykey
    data
    text
    <p>Here is the algorithm which returns the position(in form of a callback) at which an item can be inserted and also update the position of the previous items.</p> <pre><code>Put the item into infinite length array (assumed), 0&lt;=index&lt;INFINITY, and for empty array largest_index_occupied = 0. ALSO largest_index_occupied is dynamically retrieved from database.(assumed). No two item can share same index. No item must be lost during any operation. indexes are in increasing order. 1. if index not provided OR index provided is greater than largest_index_occupied then put item at index : largest_index_occupied+5; 2. If index provided AND less than equals to largest_index_occupied, : a. if (No other item already exists at that index) : simply put the item at that index b. otherwise (means if a item already exists at that index) : increase the index of all items by one untill we get an empty index. and put the new item at the index actually passed by user(which must be empty now). </code></pre> <p>2.b example :</p> <p>say - shows empty index.</p> <p>previous state</p> <pre><code>0 - - - - 5 6 7 - - 10 a - - - - b c d - - e </code></pre> <p>input at index : <code>5,f</code></p> <p>new state :</p> <pre><code>0 - - - - 5 6 7 8 - 10 a - - - - f b c d - e </code></pre> <p>Noe f's new index is 5.</p> <p>My requirement is to write a code for the above in combination of async,recursion and IO operation (db update - of the index of items in case of 2.b) in nodejs.</p> <p>i am expecting <code>next(err,indexToBeInserted);</code> callback that has to called only after all the updation has taken place.</p> <p>My function block goes here :</p> <pre><code>toInsert(mongooseModel,next,indexToBeInserted) { // async code goes here. } </code></pre> <p>ps : if you have any better solution please share.</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. UScodeofnode
    1. UScodeofnode
    plurals
    1. This table or related slice is empty.
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. POasync + recursive + database-update operation with nodejs
      1. UScodeofnode
      1. VTFavorite
    1. CO`Now f's index is 5` ... but wouldn't `e` now be at 11?
      singulars
      1. POasync + recursive + database-update operation with nodejs
      1. USjcolebrand
    2. COno e will not be on 11 in this case. because there is empty state on 8 so no further shifting after 8., However in case if prev state include ALL the indexes 5 to 10 filled, then e or whatever in place of 10 will shift to 11.
      singulars
      1. POasync + recursive + database-update operation with nodejs
      1. UScodeofnode
    3. COAhhh, that's ... confusing nomenclature, but I see what you're after there.
      singulars
      1. POasync + recursive + database-update operation with nodejs
      1. USjcolebrand
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload