Updated offset

Author: Jared Dunham

src/Illuminate/Database/Query/Grammars/SqlServerGrammar.php

@@ -19,6 +19,25 @@ class SqlServerGrammar extends Grammar
         '&', '&=', '|', '|=', '^', '^=',
     ];
 
+    /**
+     * The components that make up a select clause.
+     *
+     * @var string[]
+     */
+    protected $selectComponents = [
+        'aggregate',
+        'columns',
+        'from',
+        'joins',
+        'wheres',
+        'groups',
+        'havings',
+        'orders',
+        'offset',
+        'limit',
+        'lock',
+    ];
+
     /**
      * Compile a select query into SQL.
      *
@@ -27,26 +46,12 @@ class SqlServerGrammar extends Grammar
      */
     public function compileSelect(Builder $query)
     {
-        if (! $query->offset) {
-            return parent::compileSelect($query);
-        }
-
-        if (is_null($query->columns)) {
-            $query->columns = ['*'];
+        // An ORDER BY clause is required for offset to work
+        if($query->offset && empty($query->orders)){
+            $query->orders[] = ['sql' => '(SELECT 0)'];
         }
 
-        $components = $this->compileComponents($query);
-
-        if (! empty($components['orders'])) {
-            return parent::compileSelect($query)." offset {$query->offset} rows fetch next {$query->limit} rows only";
-        }
-
-        // If an offset is present on the query, we will need to wrap the query in
-        // a big "ANSI" offset syntax block. This is very nasty compared to the
-        // other database systems but is necessary for implementing features.
-        return $this->compileAnsiOffset(
-            $query, $components
-        );
+        return parent::compileSelect($query);
     }
 
     /**
@@ -235,69 +240,6 @@ protected function compileHavingBitwise($having)
         return '('.$column.' '.$having['operator'].' '.$parameter.') != 0';
     }
 
-    /**
-     * Create a full ANSI offset clause for the query.
-     *
-     * @param  \Illuminate\Database\Query\Builder  $query
-     * @param  array  $components
-     * @return string
-     */
-    protected function compileAnsiOffset(Builder $query, $components)
-    {
-        // An ORDER BY clause is required to make this offset query work, so if one does
-        // not exist we'll just create a dummy clause to trick the database and so it
-        // does not complain about the queries for not having an "order by" clause.
-        if (empty($components['orders'])) {
-            $components['orders'] = 'order by (select 0)';
-        }
-
-        // We need to add the row number to the query so we can compare it to the offset
-        // and limit values given for the statements. So we will add an expression to
-        // the "select" that will give back the row numbers on each of the records.
-        $components['columns'] .= $this->compileOver($components['orders']);
-
-        unset($components['orders']);
-
-        if ($this->queryOrderContainsSubquery($query)) {
-            $query->bindings = $this->sortBindingsForSubqueryOrderBy($query);
-        }
-
-        // Next we need to calculate the constraints that should be placed on the query
-        // to get the right offset and limit from our query but if there is no limit
-        // set we will just handle the offset only since that is all that matters.
-        $sql = $this->concatenate($components);
-
-        return $this->compileTableExpression($sql, $query);
-    }
-
-    /**
-     * Compile the over statement for a table expression.
-     *
-     * @param  string  $orderings
-     * @return string
-     */
-    protected function compileOver($orderings)
-    {
-        return ", row_number() over ({$orderings}) as row_num";
-    }
-
-    /**
-     * Determine if the query's order by clauses contain a subquery.
-     *
-     * @param  \Illuminate\Database\Query\Builder  $query
-     * @return bool
-     */
-    protected function queryOrderContainsSubquery($query)
-    {
-        if (! is_array($query->orders)) {
-            return false;
-        }
-
-        return Arr::first($query->orders, function ($value) {
-            return $this->isExpression($value['column'] ?? null);
-        }, false) !== false;
-    }
-
     /**
      * Move the order bindings to be after the "select" statement to account for an order by subquery.
      *
@@ -311,20 +253,6 @@ protected function sortBindingsForSubqueryOrderBy($query)
         });
     }
 
-    /**
-     * Compile a common table expression for a query.
-     *
-     * @param  string  $sql
-     * @param  \Illuminate\Database\Query\Builder  $query
-     * @return string
-     */
-    protected function compileTableExpression($sql, $query)
-    {
-        $constraint = $this->compileRowConstraint($query);
-
-        return "select * from ({$sql}) as temp_table where row_num {$constraint} order by row_num";
-    }
-
     /**
      * Compile the limit / offset row constraint for a query.
      *
@@ -381,6 +309,10 @@ public function compileRandom($seed)
      */
     protected function compileLimit(Builder $query, $limit)
     {
+        if($limit && $query->offset > 0){
+            return "fetch next {$limit} rows only";
+        }
+
         return '';
     }
 
@@ -393,6 +325,10 @@ protected function compileLimit(Builder $query, $limit)
      */
     protected function compileOffset(Builder $query, $offset)
     {
+        if($offset){
+            return "offset {$offset} rows";
+        }
+
         return '';
     }
 

tests/Database/DatabaseQueryBuilderTest.php

@@ -3502,19 +3502,18 @@ public function testSqlServerLimitsAndOffsets()
         $this->assertSame('select top 10 * from [users]', $builder->toSql());
 
         $builder = $this->getSqlServerBuilder();
-        $builder->select('*')->from('users')->skip(10);
-        $this->assertSame('select * from (select *, row_number() over (order by (select 0)) as row_num from [users]) as temp_table where row_num >= 11 order by row_num', $builder->toSql());
+        $builder->select('*')->from('users')->skip(10)->orderBy('email', 'desc');
+        $this->assertSame('select * from [users] order by [email] desc offset 10 rows', $builder->toSql());
 
         $builder = $this->getSqlServerBuilder();
         $builder->select('*')->from('users')->skip(10)->take(10);
-        $this->assertSame('select * from (select *, row_number() over (order by (select 0)) as row_num from [users]) as temp_table where row_num between 11 and 20 order by row_num', $builder->toSql());
+        $this->assertSame('select * from [users] order by (SELECT 0) offset 10 rows fetch next 10 rows only', $builder->toSql());
 
         $builder = $this->getSqlServerBuilder();
         $builder->select('*')->from('users')->skip(11)->take(10)->orderBy('email', 'desc');
         $this->assertSame('select * from [users] order by [email] desc offset 11 rows fetch next 10 rows only', $builder->toSql());
 
         $builder = $this->getSqlServerBuilder();
-        $subQueryBuilder = $this->getSqlServerBuilder();
         $subQuery = function ($query) {
             return $query->select('created_at')->from('logins')->where('users.name', 'nameBinding')->whereColumn('user_id', 'users.id')->limit(1);
         };