fix(snowflake/bigquery/athena): ensure that timestamp casting works (#11135)

Author: cpcloud

ibis/backends/sql/compilers/athena.py

@@ -4,6 +4,7 @@
 
 from sqlglot.dialects import Athena
 
+import ibis.expr.datatypes as dt
 import ibis.expr.operations as ops
 from ibis.backends.sql.compilers.trino import TrinoCompiler
 from ibis.backends.sql.datatypes import AthenaType
@@ -36,5 +37,16 @@ class AthenaCompiler(TrinoCompiler):
     def _gen_valid_name(name: str) -> str:
         return "_".join(map(str.strip, _NAME_REGEX.findall(name))) or "tmp"
 
+    def visit_Cast(self, op, *, arg, to):
+        from_ = op.arg.dtype
+        if from_.is_numeric() and to.is_timestamp():
+            if from_.is_integer():
+                return self.f.from_unixtime(arg)
+            elif from_.is_floating():
+                return self.f.from_unixtime(self.cast(arg, dt.Decimal(38, 9)))
+            else:
+                return self.f.from_unixtime(arg)
+        return super().visit_Cast(op, arg=arg, to=to)
+
 
 compiler = AthenaCompiler()

ibis/backends/sql/compilers/bigquery/__init__.py

@@ -610,7 +610,7 @@ def visit_Cast(self, op, *, arg, to):
         elif from_.is_numeric() and to.is_timestamp():
             if from_.is_integer():
                 return self.f.timestamp_seconds(arg)
-            return self.f.timestamp_micros(arg * 1_000_000)
+            return self.f.timestamp_micros(self.cast(arg * 1_000_000, dt.int64))
         elif from_.is_interval() and to.is_integer():
             if from_.unit in {
                 IntervalUnit.WEEK,

ibis/backends/sql/compilers/snowflake.py

@@ -300,10 +300,15 @@ def visit_Arbitrary(self, op, *, arg, where):
         return self.f.get(self.agg.array_agg(arg, where=where), 0)
 
     def visit_Cast(self, op, *, arg, to):
+        from_ = op.arg.dtype
         if to.is_struct() or to.is_map():
             return self.if_(self.f.is_object(arg), arg, NULL)
         elif to.is_array():
             return self.if_(self.f.is_array(arg), arg, NULL)
+        elif from_.is_numeric() and to.is_timestamp():
+            if from_.is_integer():
+                return self.f.to_timestamp(self.f.to_decimal(arg), 0)
+            return self.f.to_timestamp(self.f.to_decimal(arg * 1_000_000), 6)
         return super().visit_Cast(op, arg=arg, to=to)
 
     def visit_IsNan(self, op, *, arg):

ibis/backends/sql/compilers/trino.py

@@ -556,7 +556,13 @@ def visit_ArrayIndex(self, op, *, arg, index):
     def visit_Cast(self, op, *, arg, to):
         from_ = op.arg.dtype
         if from_.is_numeric() and to.is_timestamp():
-            return self.f.from_unixtime(arg, to.timezone or "UTC")
+            tz = to.timezone or "UTC"
+            if from_.is_integer():
+                return self.f.from_unixtime(arg, tz)
+            else:
+                return self.f.from_unixtime_nanos(
+                    self.cast(arg, dt.Decimal(38, 9)) * 1_000_000_000
+                )
         return super().visit_Cast(op, arg=arg, to=to)
 
     def visit_CountDistinctStar(self, op, *, arg, where):