switched to Func, variety of tweaks

Author: fivetran-kwoodbeck

sqlglot/expressions/core.py

@@ -1807,8 +1807,9 @@ def output_name(self) -> str:
         return self.name
 
 
-class DynamicIdentifier(Expression):
-    arg_types = {"this": True}
+# https://docs.snowflake.com/en/sql-reference/identifier-literal
+class DynamicIdentifier(Expression, Func):
+    pass
 
 
 class Opclass(Expression):

sqlglot/generator.py

@@ -9,6 +9,7 @@
 from sqlglot import exp
 from sqlglot.errors import ErrorLevel, UnsupportedError, concat_messages
 from sqlglot.expressions import apply_index_offset
+from sqlglot.expressions.core import maybe_parse
 from sqlglot.helper import csv, name_sequence, seq_get
 from sqlglot.jsonpath import ALL_JSON_PATH_PARTS, JSON_PATH_PART_TRANSFORMS
 from sqlglot.time import format_time
@@ -1948,7 +1949,8 @@ def index_sql(self, expression: exp.Index) -> str:
     def dynamicidentifier_sql(self, expression: exp.DynamicIdentifier) -> str:
         this = expression.this
         if this and this.is_string:
-            return this.name
+            return maybe_parse(this.name).sql(self.dialect)
+        self.unsupported("IDENTIFIER() with non-literal arguments is not supported")
         return self.func("IDENTIFIER", this)
 
     def identifier_sql(self, expression: exp.Identifier) -> str:

sqlglot/generators/snowflake.py

@@ -475,6 +475,7 @@ class SnowflakeGenerator(generator.Generator):
         exp.DayOfWeekIso: rename_func("DAYOFWEEKISO"),
         exp.DayOfYear: rename_func("DAYOFYEAR"),
         exp.DotProduct: rename_func("VECTOR_INNER_PRODUCT"),
+        exp.DynamicIdentifier: rename_func("IDENTIFIER"),
         exp.Explode: rename_func("FLATTEN"),
         exp.Extract: lambda self, e: self.func(
             "DATE_PART", map_date_part(e.this, self.dialect), e.expression
@@ -616,9 +617,6 @@ class SnowflakeGenerator(generator.Generator):
         ),
     }
 
-    def dynamicidentifier_sql(self, expression: exp.DynamicIdentifier) -> str:
-        return self.func("IDENTIFIER", expression.this)
-
     def sortarray_sql(self, expression: exp.SortArray) -> str:
         asc = expression.args.get("asc")
         nulls_first = expression.args.get("nulls_first")

sqlglot/parsers/snowflake.py

@@ -723,6 +723,7 @@ class SnowflakeParser(parser.Parser):
             expression=seq_get(args, 1) or exp.Literal.string(" "),
         ),
         "SYSTIMESTAMP": exp.CurrentTimestamp.from_arg_list,
+        "IDENTIFIER": exp.DynamicIdentifier.from_arg_list,
         "UNICODE": lambda args: exp.Unicode(this=seq_get(args, 0), empty_is_zero=True),
         "WEEKISO": exp.WeekOfYear.from_arg_list,
         "WEEKOFYEAR": exp.Week.from_arg_list,
@@ -733,7 +734,6 @@ class SnowflakeParser(parser.Parser):
         **parser.Parser.FUNCTION_PARSERS,
         "DATE_PART": lambda self: self._parse_date_part(),
         "DIRECTORY": lambda self: self._parse_directory(),
-        "IDENTIFIER": lambda self: self._parse_identifier_function(),
         "OBJECT_CONSTRUCT_KEEP_NULL": lambda self: self._parse_json_object(),
         "LISTAGG": lambda self: self._parse_string_agg(),
         "SEMANTIC_VIEW": lambda self: self._parse_semantic_view(),
@@ -1143,13 +1143,6 @@ def _parse_table(
 
         return table
 
-    def _fold_identifier_literal(self, arg: exp.Expr | None) -> exp.Expr:
-        return self.expression(exp.DynamicIdentifier(this=arg))
-
-    def _parse_identifier_function(self) -> exp.Expr:
-        arg = self._parse_string() or super()._parse_id_var()
-        return self._fold_identifier_literal(arg)
-
     def _parse_id_var(
         self,
         any_token: bool = True,
@@ -1160,7 +1153,7 @@ def _parse_id_var(
                 super()._parse_id_var(any_token=any_token, tokens=tokens) or self._parse_string()
             )
             self._match_r_paren()
-            return self._fold_identifier_literal(identifier)
+            return self.expression(exp.DynamicIdentifier(this=identifier))
 
         return super()._parse_id_var(any_token=any_token, tokens=tokens)