Databases
StackOverflow2013
Postsdbo
POsql question .. how can i dynamically add columns to a sql query result set?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POsql question .. how can i dynamically add columns to a sql query result set?
    primarykey
    data
    text
    <p>I am writing a report to return details about an object ('files') in my database. My application lets users create their own flags for use against file objects. Flags basically consist of a name, then flag instances store a bit value to indicate whether it is set for the parent file object.</p> <p>I want to write a query that returns one row per file in the database, where the first few columns in the result set contain the file details (id, name, size etc) and the remaining columns are the flag names, with bit values returned to indicate whether the flag is set for the given file row.</p> <p>Does that make sense? How do i go about writing the query?</p> <p>Thanks for any help.</p> <p>Edit: Clarification..</p> <p>As part of this query, I need to run a sub query that returns the flags that have been created by the user (I do not know these at design time), then incorporate a check for each flag value in the main query to return details about the files. </p> <p>Simplified schema as follows:</p> <ul> <li>File {Id, Name}</li> <li>Flag {Id, Name}</li> <li>FileFlags {FileId, FlagId} - a row in this table indicates that the flag is set for the file</li> </ul> <p>I need the query to return a result set with columns something like this:</p> <p><strong>FileId</strong> <strong>FileName</strong> <strong>Flag1Name</strong> <strong>Flag2Name</strong> .... <strong>FlagNName</strong></p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USMalcomTucker
    1. USMalcomTucker
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. This table or related slice is empty.
 

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