sql server - How to handle NULL values in multiple SQL table joins -

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i have sql query pulls data 4 tables if there's no data in third table (sc_featurecart) query returns no data.

i understand columns containing null not match values when creating join, therefore they're excluded result set still want able return values first 2 tables, sc_numbercart , sc_packages can suggest how can achieve this???

my sql query is:

select sc_numbercart.number, sc_packages.pkgname, sc_features.featurename   sc_numbercart  join sc_packages on sc_numbercart.pkgid = sc_packages.pkgid  join sc_featurecart on sc_numbercart.numberid = sc_featurecart.numberid  , sc_numbercart.recordid = sc_featurecart.recordid  join sc_features  on sc_featurecart.featureid = sc_features.featureid  sc_numbercart.cpyid = @cpyid

i can see , display result using sql query if there's data sat in sc_featurecart table illustrated below.

<table id="t2">       <tr>         <th>number</th>         <th>pkgname</th>         <th>featurename</th>       </tr>       <tr>         <td>01157710125</td>         <td>01 / 02 medium (landline)</td>         <td>call whisper</td>       </tr>     </table>

many thanks,

chris

use left join denote want results left table if there's no match in right table.

select sc_numbercart.number, sc_packages.pkgname, sc_features.featurename   sc_numbercart  left join sc_packages on sc_numbercart.pkgid = sc_packages.pkgid  left join sc_featurecart on sc_numbercart.numberid = sc_featurecart.numberid                              , sc_numbercart.recordid = sc_featurecart.recordid  left join sc_features on sc_featurecart.featureid = sc_features.featureid  sc_numbercart.cpyid = @cpyid

here's explanation of different types of joins.


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