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diff --git a/lib/SQL/Abstract/Reference.pm b/lib/SQL/Abstract/Reference.pm
index 771d222..fd29f33 100644
--- a/lib/SQL/Abstract/Reference.pm
+++ b/lib/SQL/Abstract/Reference.pm
@@ -912,4 +912,215 @@ Expands to a bind node with the currently applicable column name if known:
   foo = ?
   [ 3 ]
 
+=head1 Query Types
+
+=head2 select
+
+A select node accepts select, from, where and order_by clauses.
+
+The select clause is expanded as a list expression with a -ident default:
+
+  # expr
+  { -select => { _ => [ 'foo', 'bar', { -count => 'baz' } ] } }
+
+  # aqt
+  { -select => { select => { -op => [
+          ',', { -ident => [ 'foo' ] }, { -ident => [ 'bar' ] },
+          { -func => [ 'count', { -ident => [ 'baz' ] } ] },
+  ] } } }
+
+  # query
+  SELECT foo, bar, COUNT(baz)
+  []
+
+The from clause is expanded as a list expression with a -ident default:
+
+  # expr
+  { -select => {
+      from => [ 'schema1.table1', { -ident => [ 'schema2', 'table2' ] } ]
+  } }
+
+  # aqt
+  { -select => { from => { -from_list => [
+          { -ident => [ 'schema1', 'table1' ] },
+          { -ident => [ 'schema2', 'table2' ] },
+  ] } } }
+
+  # query
+  FROM schema1.table1, schema2.table2
+  []
+
+The where clause is expanded as a plain expression:
+
+  # expr
+  { -select => { where => { foo => 3 } } }
+
+  # aqt
+  { -select => { where => {
+        -op => [ '=', { -ident => [ 'foo' ] }, { -bind => [ 'foo', 3 ] } ]
+  } } }
+
+  # query
+  WHERE foo = ?
+  [ 3 ]
+
+The order_by clause expands as a list expression at top level, but a hashref
+element may be either an expr or a hashpair with key -asc or -desc to indicate
+an order by direction:
+
+  # expr
+  { -select =>
+      { order_by => [ 'foo', { -desc => 'bar' }, { -max => 'baz' } ] }
+  }
+
+  # aqt
+  { -select => { order_by => { -op => [
+          ',', { -ident => [ 'foo' ] }, {
+            -op => [ ',', { -op => [ 'desc', { -ident => [ 'bar' ] } ] } ]
+          }, { -func => [ 'max', { -ident => [ 'baz' ] } ] },
+  ] } } }
+
+  # query
+  ORDER BY foo, bar DESC, MAX(baz)
+  []
+
+=head2
+
+An insert node accepts an into/target clause, a fields clause, a values/from
+clause, and a returning clause.
+
+The target clause is expanded with an ident default.
+
+The fields clause is expanded as a list expression if an arrayref, and
+otherwise passed through.
+
+The from clause may either be an expr, a literal, an arrayref of column
+values, or a hashref mapping colum names to values.
+
+The returning clause is expanded as a list expr with an ident default.
+
+  # expr
+  { -insert => {
+      into => 'foo',
+      returning => 'id',
+      values => { bar => 'yay', baz => 'argh' },
+  } }
+
+  # aqt
+  { -insert => {
+      fields =>
+        { -row => [ { -ident => [ 'bar' ] }, { -ident => [ 'baz' ] } ] },
+      from => { -values => [ { -row => [
+              { -bind => [ 'bar', 'yay' ] },
+              { -bind => [ 'baz', 'argh' ] },
+      ] } ] },
+      returning => { -op => [ ',', { -ident => [ 'id' ] } ] },
+      target => { -op => [ ',', { -ident => [ 'foo' ] } ] },
+  } }
+
+  # query
+  INSERT INTO foo (bar, baz) VALUES (?, ?) RETURNING id
+  [ 'yay', 'argh' ]
+
+  # expr
+  { -insert => {
+      fields => [ 'bar', 'baz' ],
+      from => { -select => { _ => [ 'bar', 'baz' ], from => 'other' } },
+      into => 'foo',
+  } }
+
+  # aqt
+  { -insert => {
+      fields => { -row => [ { -op =>
+              [ ',', { -ident => [ 'bar' ] }, { -ident => [ 'baz' ] } ]
+      } ] },
+      from => { -select => {
+          from => { -from_list => [ { -ident => [ 'other' ] } ] },
+          select => { -op =>
+              [ ',', { -ident => [ 'bar' ] }, { -ident => [ 'baz' ] } ]
+          },
+      } },
+      target => { -op => [ ',', { -ident => [ 'foo' ] } ] },
+  } }
+
+  # query
+  INSERT INTO foo (bar, baz) SELECT bar, baz FROM other
+  []
+
+=head2 update
+
+An update node accepts update/target (either may be used at expansion time),
+set, where, and returning clauses.
+
+The target clause is expanded with an ident default.
+
+The set clause (if not already a list expr) is expanded as a hashref where
+the keys are identifiers to be set and the values are exprs/values.
+
+The where clauses is expanded as a normal expr.
+
+The returning clause is expanded as a list expr with an ident default.
+
+  # expr
+  { -update => {
+      _ => 'foo',
+      returning => [ 'id', 'baz' ],
+      set => { bar => 3, baz => { baz => { '+' => 1 } } },
+      where => { -not => { -ident => 'quux' } },
+  } }
+
+  # aqt
+  { -update => {
+      returning =>
+        {
+          -op => [ ',', { -ident => [ 'id' ] }, { -ident => [ 'baz' ] } ]
+        },
+      set => { -op => [
+          ',', { -op =>
+              [ '=', { -ident => [ 'bar' ] }, { -bind => [ 'bar', 3 ] } ]
+          }, { -op => [
+              '=', { -ident => [ 'baz' ] }, { -op => [
+                  '+', { -ident => [ 'baz' ] },
+                  { -bind => [ 'baz', 1 ] },
+              ] },
+          ] },
+      ] },
+      target => { -from_list => [ { -ident => [ 'foo' ] } ] },
+      where => { -op => [ 'not', { -ident => [ 'quux' ] } ] },
+  } }
+
+  # query
+  UPDATE foo SET bar = ?, baz = baz + ? WHERE (NOT quux) RETURNING id, baz
+  [ 3, 1 ]
+
+=head2 delete
+
+delete accepts from/target, where, and returning clauses.
+
+The target clause is expanded with an ident default.
+
+The where clauses is expanded as a normal expr.
+
+The returning clause is expanded as a list expr with an ident default.
+
+  # expr
+  { -delete => {
+      from => 'foo',
+      returning => 'id',
+      where => { bar => { '<' => 10 } },
+  } }
+
+  # aqt
+  { -delete => {
+      returning => { -op => [ ',', { -ident => [ 'id' ] } ] },
+      target => { -op => [ ',', { -ident => [ 'foo' ] } ] },
+      where => { -op =>
+          [ '<', { -ident => [ 'bar' ] }, { -bind => [ 'bar', 10 ] } ]
+      },
+  } }
+
+  # query
+  DELETE FROM foo WHERE bar < ? RETURNING id
+  [ 10 ]
+
 =cut