From 0ab34cb36cef98a58b1e04254f3a92cdf09af389 Mon Sep 17 00:00:00 2001
From: Chelsea Lin <chelsealin@google.com>
Date: Tue, 6 Feb 2024 00:19:46 +0000
Subject: [PATCH] prototype as_table

---
 ibis/backends/base/sqlglot/compiler.py |  8 +++++++-
 ibis/backends/tests/test_array.py      |  8 ++++++++
 ibis/expr/operations/arrays.py         | 18 ++++++++++++++++++
 ibis/expr/types/arrays.py              | 16 ++++++++++++++--
 4 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/ibis/backends/base/sqlglot/compiler.py b/ibis/backends/base/sqlglot/compiler.py
index f54188c5daba..4599cb4d4965 100644
--- a/ibis/backends/base/sqlglot/compiler.py
+++ b/ibis/backends/base/sqlglot/compiler.py
@@ -276,7 +276,7 @@ def fn(node, _, **kwargs):
             try:
                 return result.subquery(alias)
             except AttributeError:
-                return result.as_(alias, quoted=self.quoted)
+                return result.as_(alias, quoted=self.quoted, table=[alias.name])
 
         # apply translate rules in topological order
         results = op.map(fn)
@@ -1011,6 +1011,12 @@ def visit_DatabaseTable(
             name, db=namespace.schema, catalog=namespace.database, quoted=self.quoted
         )
 
+    @visit_node.register(ops.ArrayTable)
+    def visit_ArrayTable(
+        self, op, *, col
+    ) -> sg.Table:
+        return sge.Unnest(expressions=[col], offset=None)
+
     @visit_node.register(ops.SelfReference)
     def visit_SelfReference(self, op, *, parent, identifier):
         return parent
diff --git a/ibis/backends/tests/test_array.py b/ibis/backends/tests/test_array.py
index 2d203c2c9f92..6623e532e6d0 100644
--- a/ibis/backends/tests/test_array.py
+++ b/ibis/backends/tests/test_array.py
@@ -325,6 +325,14 @@ def test_unnest_idempotent(backend):
     tm.assert_frame_equal(result, expected)
 
 
+@builtin_array
+@pytest.mark.notimpl("dask", raises=ValueError)
+@pytest.mark.notimpl(["datafusion"], raises=com.OperationNotDefinedError)
+def test_as_table(backend):
+    array_types = backend.array_types
+    print(ibis.to_sql(array_types.cross_join(array_types.x.as_table())).__repr__())
+
+
 @builtin_array
 @pytest.mark.notimpl(["datafusion", "flink"], raises=com.OperationNotDefinedError)
 @pytest.mark.broken(
diff --git a/ibis/expr/operations/arrays.py b/ibis/expr/operations/arrays.py
index 68ee711a2da6..9a585ea5be21 100644
--- a/ibis/expr/operations/arrays.py
+++ b/ibis/expr/operations/arrays.py
@@ -8,8 +8,11 @@
 import ibis.expr.datatypes as dt
 import ibis.expr.rules as rlz
 from ibis.common.annotations import attribute
+from ibis.common.collections import FrozenDict
 from ibis.common.typing import VarTuple  # noqa: TCH001
 from ibis.expr.operations.core import Unary, Value
+from ibis.expr.operations.relations import Relation, Simple
+from ibis.expr.schema import Schema
 
 
 @public
@@ -111,6 +114,21 @@ def dtype(self):
         return self.arg.dtype.value_type
 
 
+@public
+class ArrayTable(Relation):
+    # -> DatabaseTable
+    """A table sourced from the result set of a select query."""
+    col: Value[dt.Array]
+    
+    @attribute
+    def values(self):
+        return FrozenDict()
+
+    @property
+    def schema(self) -> Schema:
+        return Schema.from_tuples(zip([self.col.name], [self.col.dtype.value_type]))
+
+
 @public
 class ArrayContains(Value):
     arg: Value[dt.Array]
diff --git a/ibis/expr/types/arrays.py b/ibis/expr/types/arrays.py
index 5a390b2919b1..79e4fa3954ec 100644
--- a/ibis/expr/types/arrays.py
+++ b/ibis/expr/types/arrays.py
@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+from typing import TYPE_CHECKING, Callable, Iterable, Optional
 import inspect
 from typing import TYPE_CHECKING, Callable
 
@@ -305,12 +306,23 @@ def unnest(self) -> ir.Value:
         ir.Value
             Unnested array
         """
-        expr = ops.Unnest(self).to_expr()
+        expr = ops.Unnest(self).to_expr()     # -> UNNEST(t0.x) AS AsTable_x
         try:
-            return expr.name(self.get_name())
+            return expr.name(self.get_name()) # -> UNNEST(t0.x) AS x
         except com.ExpressionError:
             return expr
 
+    def as_table(
+            self,
+            offset_name: Optional[str] = None,
+        ) -> ir.Table:
+        """TODO(chelsealin)
+        """
+
+        # TODO(chelsealin) add offset_name
+        expr = ops.ArrayTable(self).to_expr()
+        return expr
+
     def join(self, sep: str | ir.StringValue) -> ir.StringValue:
         """Join the elements of this array expression with `sep`.