diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_aggregate_params_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_aggregate_params_validation.snap
index a30ea406..0d68f0e2 100644
--- a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_aggregate_params_validation.snap
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_aggregate_params_validation.snap
@@ -2,103 +2,124 @@
 source: crates/squawk_syntax/src/test.rs
 input_file: crates/squawk_syntax/test_data/validation/alter_aggregate_params.sql
 ---
-SOURCE_FILE@0..120
+SOURCE_FILE@0..166
   COMMENT@0..38 "-- can't have out par ..."
   WHITESPACE@38..39 "\n"
-  CREATE_AGGREGATE@39..119
-    CREATE_KW@39..45 "create"
-    WHITESPACE@45..46 " "
-    AGGREGATE_KW@46..55 "aggregate"
-    WHITESPACE@55..56 " "
-    AGGREGATE_NAME@56..57
-      PATH@56..57
-        PATH_SEGMENT@56..57
-          IDENT@56..57 "a"
-    PARAM_LIST@57..89
-      L_PAREN@57..58 "("
-      PARAM@58..62
-        PARAM_IN@58..60
-          IN_KW@58..60 "in"
-        WHITESPACE@60..61 " "
-        PATH_TYPE@61..62
-          PATH_REF@61..62
-            PATH_SEGMENT_REF@61..62
-              IDENT@61..62 "x"
-      COMMA@62..63 ","
-      WHITESPACE@63..64 " "
-      PARAM@64..69
-        PARAM_OUT@64..67
-          OUT_KW@64..67 "out"
-        WHITESPACE@67..68 " "
-        PATH_TYPE@68..69
-          PATH_REF@68..69
-            PATH_SEGMENT_REF@68..69
-              IDENT@68..69 "y"
-      COMMA@69..70 ","
-      WHITESPACE@70..71 " "
-      PARAM@71..78
-        PARAM_IN_OUT@71..76
-          INOUT_KW@71..76 "inout"
-        WHITESPACE@76..77 " "
-        PATH_TYPE@77..78
-          PATH_REF@77..78
-            PATH_SEGMENT_REF@77..78
-              IDENT@77..78 "z"
-      COMMA@78..79 ","
-      WHITESPACE@79..80 " "
-      PARAM@80..88
-        PARAM_IN_OUT@80..86
-          IN_KW@80..82 "in"
-          WHITESPACE@82..83 " "
-          OUT_KW@83..86 "out"
-        WHITESPACE@86..87 " "
-        PATH_TYPE@87..88
-          PATH_REF@87..88
-            PATH_SEGMENT_REF@87..88
-              IDENT@87..88 "w"
-      R_PAREN@88..89 ")"
-    WHITESPACE@89..90 " "
-    ATTRIBUTE_LIST@90..118
-      L_PAREN@90..91 "("
-      WHITESPACE@91..94 "\n  "
-      ATTRIBUTE_OPTION@94..103
-        ATTRIBUTE_NAME@94..99
-          IDENT@94..99 "sfunc"
-        WHITESPACE@99..100 " "
-        EQ@100..101 "="
-        WHITESPACE@101..102 " "
-        ATTRIBUTE_VALUE@102..103
-          PATH_TYPE@102..103
-            PATH_REF@102..103
-              PATH_SEGMENT_REF@102..103
-                IDENT@102..103 "f"
-      COMMA@103..104 ","
-      WHITESPACE@104..107 "\n  "
-      ATTRIBUTE_OPTION@107..116
-        ATTRIBUTE_NAME@107..112
-          IDENT@107..112 "stype"
-        WHITESPACE@112..113 " "
-        EQ@113..114 "="
-        WHITESPACE@114..115 " "
-        ATTRIBUTE_VALUE@115..116
-          PATH_TYPE@115..116
-            PATH_REF@115..116
-              PATH_SEGMENT_REF@115..116
-                IDENT@115..116 "t"
-      WHITESPACE@116..117 "\n"
-      R_PAREN@117..118 ")"
-    SEMICOLON@118..119 ";"
-  WHITESPACE@119..120 "\n"
+  ALTER_AGGREGATE@39..107
+    ALTER_KW@39..44 "alter"
+    WHITESPACE@44..45 " "
+    AGGREGATE_KW@45..54 "aggregate"
+    WHITESPACE@54..55 " "
+    AGGREGATE@55..89
+      PATH_REF@55..56
+        PATH_SEGMENT_REF@55..56
+          IDENT@55..56 "a"
+      WHITESPACE@56..57 " "
+      PARAM_LIST@57..89
+        L_PAREN@57..58 "("
+        PARAM@58..62
+          PARAM_IN@58..60
+            IN_KW@58..60 "in"
+          WHITESPACE@60..61 " "
+          PATH_TYPE@61..62
+            PATH_REF@61..62
+              PATH_SEGMENT_REF@61..62
+                IDENT@61..62 "t"
+        COMMA@62..63 ","
+        WHITESPACE@63..64 " "
+        PARAM@64..69
+          PARAM_OUT@64..67
+            OUT_KW@64..67 "out"
+          WHITESPACE@67..68 " "
+          PATH_TYPE@68..69
+            PATH_REF@68..69
+              PATH_SEGMENT_REF@68..69
+                IDENT@68..69 "u"
+        COMMA@69..70 ","
+        WHITESPACE@70..71 " "
+        PARAM@71..78
+          PARAM_IN_OUT@71..76
+            INOUT_KW@71..76 "inout"
+          WHITESPACE@76..77 " "
+          PATH_TYPE@77..78
+            PATH_REF@77..78
+              PATH_SEGMENT_REF@77..78
+                IDENT@77..78 "v"
+        COMMA@78..79 ","
+        WHITESPACE@79..80 " "
+        PARAM@80..88
+          PARAM_IN_OUT@80..86
+            IN_KW@80..82 "in"
+            WHITESPACE@82..83 " "
+            OUT_KW@83..86 "out"
+          WHITESPACE@86..87 " "
+          PATH_TYPE@87..88
+            PATH_REF@87..88
+              PATH_SEGMENT_REF@87..88
+                IDENT@87..88 "w"
+        R_PAREN@88..89 ")"
+    WHITESPACE@89..94 "\n    "
+    SET_SCHEMA@94..106
+      SET_KW@94..97 "set"
+      WHITESPACE@97..98 " "
+      SCHEMA_KW@98..104 "schema"
+      WHITESPACE@104..105 " "
+      SCHEMA_REF@105..106
+        IDENT@105..106 "s"
+    SEMICOLON@106..107 ";"
+  WHITESPACE@107..109 "\n\n"
+  ALTER_AGGREGATE@109..165
+    ALTER_KW@109..114 "alter"
+    WHITESPACE@114..115 " "
+    AGGREGATE_KW@115..124 "aggregate"
+    WHITESPACE@124..125 " "
+    AGGREGATE@125..151
+      PATH_REF@125..126
+        PATH_SEGMENT_REF@125..126
+          IDENT@125..126 "a"
+      PARAM_LIST@126..151
+        L_PAREN@126..127 "("
+        PARAM@127..150
+          PARAM_NAME@127..132
+            VALUE_KW@127..132 "value"
+          WHITESPACE@132..133 " "
+          PATH_TYPE@133..140
+            PATH_REF@133..140
+              PATH_SEGMENT_REF@133..140
+                INTEGER_KW@133..140 "integer"
+          WHITESPACE@140..141 " "
+          PARAM_DEFAULT@141..150
+            DEFAULT_KW@141..148 "default"
+            WHITESPACE@148..149 " "
+            LITERAL@149..150
+              INT_NUMBER@149..150 "1"
+        R_PAREN@150..151 ")"
+    WHITESPACE@151..152 " "
+    AGGREGATE_RENAME_TO@152..164
+      RENAME_KW@152..158 "rename"
+      WHITESPACE@158..159 " "
+      TO_KW@159..161 "to"
+      WHITESPACE@161..162 " "
+      AGGREGATE_NAME@162..164
+        PATH@162..164
+          PATH_SEGMENT@162..164
+            IDENT@162..164 "a2"
+    SEMICOLON@164..165 ";"
+  WHITESPACE@165..166 "\n"
 
 error[syntax-error]: Out params are not allowed with aggregates.
   ╭▸ 
-2 │ create aggregate a(in x, out y, inout z, in out w) (
+2 │ alter aggregate a (in t, out u, inout v, in out w)
   ╰╴                         ━━━
 error[syntax-error]: In Out params are not allowed with aggregates.
   ╭▸ 
-2 │ create aggregate a(in x, out y, inout z, in out w) (
+2 │ alter aggregate a (in t, out u, inout v, in out w)
   ╰╴                                ━━━━━
 error[syntax-error]: In Out params are not allowed with aggregates.
   ╭▸ 
-2 │ create aggregate a(in x, out y, inout z, in out w) (
+2 │ alter aggregate a (in t, out u, inout v, in out w)
   ╰╴                                         ━━━━━━
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+5 │ alter aggregate a(value integer default 1) rename to a2;
+  ╰╴                                ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_function_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_function_validation.snap
new file mode 100644
index 00000000..01682223
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_function_validation.snap
@@ -0,0 +1,49 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/alter_function.sql
+---
+SOURCE_FILE@0..56
+  ALTER_FUNCTION@0..55
+    ALTER_KW@0..5 "alter"
+    WHITESPACE@5..6 " "
+    FUNCTION_KW@6..14 "function"
+    WHITESPACE@14..15 " "
+    FUNCTION_SIG@15..41
+      FUNCTION_NAME_REF@15..16
+        PATH_REF@15..16
+          PATH_SEGMENT_REF@15..16
+            IDENT@15..16 "f"
+      PARAM_LIST@16..41
+        L_PAREN@16..17 "("
+        PARAM@17..40
+          PARAM_NAME@17..22
+            VALUE_KW@17..22 "value"
+          WHITESPACE@22..23 " "
+          PATH_TYPE@23..30
+            PATH_REF@23..30
+              PATH_SEGMENT_REF@23..30
+                INTEGER_KW@23..30 "integer"
+          WHITESPACE@30..31 " "
+          PARAM_DEFAULT@31..40
+            DEFAULT_KW@31..38 "default"
+            WHITESPACE@38..39 " "
+            LITERAL@39..40
+              INT_NUMBER@39..40 "1"
+        R_PAREN@40..41 ")"
+    WHITESPACE@41..42 " "
+    FUNCTION_RENAME_TO@42..54
+      RENAME_KW@42..48 "rename"
+      WHITESPACE@48..49 " "
+      TO_KW@49..51 "to"
+      WHITESPACE@51..52 " "
+      FUNCTION_NAME@52..54
+        PATH@52..54
+          PATH_SEGMENT@52..54
+            IDENT@52..54 "f2"
+    SEMICOLON@54..55 ";"
+  WHITESPACE@55..56 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ alter function f(value integer default 1) rename to f2;
+  ╰╴                               ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_procedure_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_procedure_validation.snap
new file mode 100644
index 00000000..5dd69635
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_procedure_validation.snap
@@ -0,0 +1,49 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/alter_procedure.sql
+---
+SOURCE_FILE@0..57
+  ALTER_PROCEDURE@0..56
+    ALTER_KW@0..5 "alter"
+    WHITESPACE@5..6 " "
+    PROCEDURE_KW@6..15 "procedure"
+    WHITESPACE@15..16 " "
+    PROCEDURE_SIG@16..42
+      PROCEDURE_NAME_REF@16..17
+        PATH_REF@16..17
+          PATH_SEGMENT_REF@16..17
+            IDENT@16..17 "p"
+      PARAM_LIST@17..42
+        L_PAREN@17..18 "("
+        PARAM@18..41
+          PARAM_NAME@18..23
+            VALUE_KW@18..23 "value"
+          WHITESPACE@23..24 " "
+          PATH_TYPE@24..31
+            PATH_REF@24..31
+              PATH_SEGMENT_REF@24..31
+                INTEGER_KW@24..31 "integer"
+          WHITESPACE@31..32 " "
+          PARAM_DEFAULT@32..41
+            DEFAULT_KW@32..39 "default"
+            WHITESPACE@39..40 " "
+            LITERAL@40..41
+              INT_NUMBER@40..41 "1"
+        R_PAREN@41..42 ")"
+    WHITESPACE@42..43 " "
+    PROCEDURE_RENAME_TO@43..55
+      RENAME_KW@43..49 "rename"
+      WHITESPACE@49..50 " "
+      TO_KW@50..52 "to"
+      WHITESPACE@52..53 " "
+      PROCEDURE_NAME@53..55
+        PATH@53..55
+          PATH_SEGMENT@53..55
+            IDENT@53..55 "p2"
+    SEMICOLON@55..56 ";"
+  WHITESPACE@56..57 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ alter procedure p(value integer default 1) rename to p2;
+  ╰╴                                ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_routine_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_routine_validation.snap
new file mode 100644
index 00000000..70521309
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_routine_validation.snap
@@ -0,0 +1,49 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/alter_routine.sql
+---
+SOURCE_FILE@0..55
+  ALTER_ROUTINE@0..54
+    ALTER_KW@0..5 "alter"
+    WHITESPACE@5..6 " "
+    ROUTINE_KW@6..13 "routine"
+    WHITESPACE@13..14 " "
+    ROUTINE_SIG@14..40
+      ROUTINE_NAME_REF@14..15
+        PATH_REF@14..15
+          PATH_SEGMENT_REF@14..15
+            IDENT@14..15 "r"
+      PARAM_LIST@15..40
+        L_PAREN@15..16 "("
+        PARAM@16..39
+          PARAM_NAME@16..21
+            VALUE_KW@16..21 "value"
+          WHITESPACE@21..22 " "
+          PATH_TYPE@22..29
+            PATH_REF@22..29
+              PATH_SEGMENT_REF@22..29
+                INTEGER_KW@22..29 "integer"
+          WHITESPACE@29..30 " "
+          PARAM_DEFAULT@30..39
+            DEFAULT_KW@30..37 "default"
+            WHITESPACE@37..38 " "
+            LITERAL@38..39
+              INT_NUMBER@38..39 "1"
+        R_PAREN@39..40 ")"
+    WHITESPACE@40..41 " "
+    ROUTINE_RENAME_TO@41..53
+      RENAME_KW@41..47 "rename"
+      WHITESPACE@47..48 " "
+      TO_KW@48..50 "to"
+      WHITESPACE@50..51 " "
+      ROUTINE_NAME@51..53
+        PATH@51..53
+          PATH_SEGMENT@51..53
+            IDENT@51..53 "r2"
+    SEMICOLON@53..54 ";"
+  WHITESPACE@54..55 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ alter routine r(value integer default 1) rename to r2;
+  ╰╴                              ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__comment_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__comment_validation.snap
new file mode 100644
index 00000000..56028b05
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__comment_validation.snap
@@ -0,0 +1,169 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/comment.sql
+---
+SOURCE_FILE@0..250
+  COMMENT_ON@0..61
+    COMMENT_KW@0..7 "comment"
+    WHITESPACE@7..8 " "
+    ON_KW@8..10 "on"
+    WHITESPACE@10..11 " "
+    OBJECT_FUNCTION@11..46
+      FUNCTION_KW@11..19 "function"
+      WHITESPACE@19..20 " "
+      FUNCTION_SIG@20..46
+        FUNCTION_NAME_REF@20..21
+          PATH_REF@20..21
+            PATH_SEGMENT_REF@20..21
+              IDENT@20..21 "f"
+        PARAM_LIST@21..46
+          L_PAREN@21..22 "("
+          PARAM@22..45
+            PARAM_NAME@22..27
+              VALUE_KW@22..27 "value"
+            WHITESPACE@27..28 " "
+            PATH_TYPE@28..35
+              PATH_REF@28..35
+                PATH_SEGMENT_REF@28..35
+                  INTEGER_KW@28..35 "integer"
+            WHITESPACE@35..36 " "
+            PARAM_DEFAULT@36..45
+              DEFAULT_KW@36..43 "default"
+              WHITESPACE@43..44 " "
+              LITERAL@44..45
+                INT_NUMBER@44..45 "1"
+          R_PAREN@45..46 ")"
+    WHITESPACE@46..47 " "
+    IS_KW@47..49 "is"
+    WHITESPACE@49..50 " "
+    LITERAL@50..60
+      STRING@50..60 "'function'"
+    SEMICOLON@60..61 ";"
+  WHITESPACE@61..62 "\n"
+  COMMENT_ON@62..125
+    COMMENT_KW@62..69 "comment"
+    WHITESPACE@69..70 " "
+    ON_KW@70..72 "on"
+    WHITESPACE@72..73 " "
+    OBJECT_PROCEDURE@73..109
+      PROCEDURE_KW@73..82 "procedure"
+      WHITESPACE@82..83 " "
+      PROCEDURE_SIG@83..109
+        PROCEDURE_NAME_REF@83..84
+          PATH_REF@83..84
+            PATH_SEGMENT_REF@83..84
+              IDENT@83..84 "p"
+        PARAM_LIST@84..109
+          L_PAREN@84..85 "("
+          PARAM@85..108
+            PARAM_NAME@85..90
+              VALUE_KW@85..90 "value"
+            WHITESPACE@90..91 " "
+            PATH_TYPE@91..98
+              PATH_REF@91..98
+                PATH_SEGMENT_REF@91..98
+                  INTEGER_KW@91..98 "integer"
+            WHITESPACE@98..99 " "
+            PARAM_DEFAULT@99..108
+              DEFAULT_KW@99..106 "default"
+              WHITESPACE@106..107 " "
+              LITERAL@107..108
+                INT_NUMBER@107..108 "1"
+          R_PAREN@108..109 ")"
+    WHITESPACE@109..110 " "
+    IS_KW@110..112 "is"
+    WHITESPACE@112..113 " "
+    LITERAL@113..124
+      STRING@113..124 "'procedure'"
+    SEMICOLON@124..125 ";"
+  WHITESPACE@125..126 "\n"
+  COMMENT_ON@126..185
+    COMMENT_KW@126..133 "comment"
+    WHITESPACE@133..134 " "
+    ON_KW@134..136 "on"
+    WHITESPACE@136..137 " "
+    OBJECT_ROUTINE@137..171
+      ROUTINE_KW@137..144 "routine"
+      WHITESPACE@144..145 " "
+      ROUTINE_SIG@145..171
+        ROUTINE_NAME_REF@145..146
+          PATH_REF@145..146
+            PATH_SEGMENT_REF@145..146
+              IDENT@145..146 "r"
+        PARAM_LIST@146..171
+          L_PAREN@146..147 "("
+          PARAM@147..170
+            PARAM_NAME@147..152
+              VALUE_KW@147..152 "value"
+            WHITESPACE@152..153 " "
+            PATH_TYPE@153..160
+              PATH_REF@153..160
+                PATH_SEGMENT_REF@153..160
+                  INTEGER_KW@153..160 "integer"
+            WHITESPACE@160..161 " "
+            PARAM_DEFAULT@161..170
+              DEFAULT_KW@161..168 "default"
+              WHITESPACE@168..169 " "
+              LITERAL@169..170
+                INT_NUMBER@169..170 "1"
+          R_PAREN@170..171 ")"
+    WHITESPACE@171..172 " "
+    IS_KW@172..174 "is"
+    WHITESPACE@174..175 " "
+    LITERAL@175..184
+      STRING@175..184 "'routine'"
+    SEMICOLON@184..185 ";"
+  WHITESPACE@185..186 "\n"
+  COMMENT_ON@186..249
+    COMMENT_KW@186..193 "comment"
+    WHITESPACE@193..194 " "
+    ON_KW@194..196 "on"
+    WHITESPACE@196..197 " "
+    OBJECT_AGGREGATE@197..233
+      AGGREGATE_KW@197..206 "aggregate"
+      WHITESPACE@206..207 " "
+      AGGREGATE@207..233
+        PATH_REF@207..208
+          PATH_SEGMENT_REF@207..208
+            IDENT@207..208 "a"
+        PARAM_LIST@208..233
+          L_PAREN@208..209 "("
+          PARAM@209..232
+            PARAM_NAME@209..214
+              VALUE_KW@209..214 "value"
+            WHITESPACE@214..215 " "
+            PATH_TYPE@215..222
+              PATH_REF@215..222
+                PATH_SEGMENT_REF@215..222
+                  INTEGER_KW@215..222 "integer"
+            WHITESPACE@222..223 " "
+            PARAM_DEFAULT@223..232
+              DEFAULT_KW@223..230 "default"
+              WHITESPACE@230..231 " "
+              LITERAL@231..232
+                INT_NUMBER@231..232 "1"
+          R_PAREN@232..233 ")"
+    WHITESPACE@233..234 " "
+    IS_KW@234..236 "is"
+    WHITESPACE@236..237 " "
+    LITERAL@237..248
+      STRING@237..248 "'aggregate'"
+    SEMICOLON@248..249 ";"
+  WHITESPACE@249..250 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ comment on function f(value integer default 1) is 'function';
+  ╰╴                                    ━━━━━━━━━
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+2 │ comment on procedure p(value integer default 1) is 'procedure';
+  ╰╴                                     ━━━━━━━━━
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+3 │ comment on routine r(value integer default 1) is 'routine';
+  ╰╴                                   ━━━━━━━━━
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+4 │ comment on aggregate a(value integer default 1) is 'aggregate';
+  ╰╴                                     ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__create_aggregate_params_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__create_aggregate_params_validation.snap
index 3e834fc8..9e066cc7 100644
--- a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__create_aggregate_params_validation.snap
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__create_aggregate_params_validation.snap
@@ -2,82 +2,243 @@
 source: crates/squawk_syntax/src/test.rs
 input_file: crates/squawk_syntax/test_data/validation/create_aggregate_params.sql
 ---
-SOURCE_FILE@0..109
+SOURCE_FILE@0..366
   COMMENT@0..38 "-- can't have out par ..."
   WHITESPACE@38..39 "\n"
-  ALTER_AGGREGATE@39..107
-    ALTER_KW@39..44 "alter"
-    WHITESPACE@44..45 " "
-    AGGREGATE_KW@45..54 "aggregate"
-    WHITESPACE@54..55 " "
-    AGGREGATE@55..89
-      PATH_REF@55..56
-        PATH_SEGMENT_REF@55..56
-          IDENT@55..56 "a"
-      WHITESPACE@56..57 " "
-      PARAM_LIST@57..89
-        L_PAREN@57..58 "("
-        PARAM@58..62
-          PARAM_IN@58..60
-            IN_KW@58..60 "in"
-          WHITESPACE@60..61 " "
-          PATH_TYPE@61..62
-            PATH_REF@61..62
-              PATH_SEGMENT_REF@61..62
-                IDENT@61..62 "t"
-        COMMA@62..63 ","
-        WHITESPACE@63..64 " "
-        PARAM@64..69
-          PARAM_OUT@64..67
-            OUT_KW@64..67 "out"
-          WHITESPACE@67..68 " "
-          PATH_TYPE@68..69
-            PATH_REF@68..69
-              PATH_SEGMENT_REF@68..69
-                IDENT@68..69 "u"
-        COMMA@69..70 ","
-        WHITESPACE@70..71 " "
-        PARAM@71..78
-          PARAM_IN_OUT@71..76
-            INOUT_KW@71..76 "inout"
-          WHITESPACE@76..77 " "
-          PATH_TYPE@77..78
-            PATH_REF@77..78
-              PATH_SEGMENT_REF@77..78
-                IDENT@77..78 "v"
-        COMMA@78..79 ","
-        WHITESPACE@79..80 " "
-        PARAM@80..88
-          PARAM_IN_OUT@80..86
-            IN_KW@80..82 "in"
-            WHITESPACE@82..83 " "
-            OUT_KW@83..86 "out"
-          WHITESPACE@86..87 " "
-          PATH_TYPE@87..88
-            PATH_REF@87..88
-              PATH_SEGMENT_REF@87..88
-                IDENT@87..88 "w"
-        R_PAREN@88..89 ")"
-    WHITESPACE@89..94 "\n    "
-    SET_SCHEMA@94..106
-      SET_KW@94..97 "set"
-      WHITESPACE@97..98 " "
-      SCHEMA_KW@98..104 "schema"
-      WHITESPACE@104..105 " "
-      SCHEMA_REF@105..106
-        IDENT@105..106 "s"
-    SEMICOLON@106..107 ";"
-  WHITESPACE@107..109 "\n\n"
+  CREATE_AGGREGATE@39..119
+    CREATE_KW@39..45 "create"
+    WHITESPACE@45..46 " "
+    AGGREGATE_KW@46..55 "aggregate"
+    WHITESPACE@55..56 " "
+    AGGREGATE_NAME@56..57
+      PATH@56..57
+        PATH_SEGMENT@56..57
+          IDENT@56..57 "a"
+    PARAM_LIST@57..89
+      L_PAREN@57..58 "("
+      PARAM@58..62
+        PARAM_IN@58..60
+          IN_KW@58..60 "in"
+        WHITESPACE@60..61 " "
+        PATH_TYPE@61..62
+          PATH_REF@61..62
+            PATH_SEGMENT_REF@61..62
+              IDENT@61..62 "x"
+      COMMA@62..63 ","
+      WHITESPACE@63..64 " "
+      PARAM@64..69
+        PARAM_OUT@64..67
+          OUT_KW@64..67 "out"
+        WHITESPACE@67..68 " "
+        PATH_TYPE@68..69
+          PATH_REF@68..69
+            PATH_SEGMENT_REF@68..69
+              IDENT@68..69 "y"
+      COMMA@69..70 ","
+      WHITESPACE@70..71 " "
+      PARAM@71..78
+        PARAM_IN_OUT@71..76
+          INOUT_KW@71..76 "inout"
+        WHITESPACE@76..77 " "
+        PATH_TYPE@77..78
+          PATH_REF@77..78
+            PATH_SEGMENT_REF@77..78
+              IDENT@77..78 "z"
+      COMMA@78..79 ","
+      WHITESPACE@79..80 " "
+      PARAM@80..88
+        PARAM_IN_OUT@80..86
+          IN_KW@80..82 "in"
+          WHITESPACE@82..83 " "
+          OUT_KW@83..86 "out"
+        WHITESPACE@86..87 " "
+        PATH_TYPE@87..88
+          PATH_REF@87..88
+            PATH_SEGMENT_REF@87..88
+              IDENT@87..88 "w"
+      R_PAREN@88..89 ")"
+    WHITESPACE@89..90 " "
+    ATTRIBUTE_LIST@90..118
+      L_PAREN@90..91 "("
+      WHITESPACE@91..94 "\n  "
+      ATTRIBUTE_OPTION@94..103
+        ATTRIBUTE_NAME@94..99
+          IDENT@94..99 "sfunc"
+        WHITESPACE@99..100 " "
+        EQ@100..101 "="
+        WHITESPACE@101..102 " "
+        ATTRIBUTE_VALUE@102..103
+          PATH_TYPE@102..103
+            PATH_REF@102..103
+              PATH_SEGMENT_REF@102..103
+                IDENT@102..103 "f"
+      COMMA@103..104 ","
+      WHITESPACE@104..107 "\n  "
+      ATTRIBUTE_OPTION@107..116
+        ATTRIBUTE_NAME@107..112
+          IDENT@107..112 "stype"
+        WHITESPACE@112..113 " "
+        EQ@113..114 "="
+        WHITESPACE@114..115 " "
+        ATTRIBUTE_VALUE@115..116
+          PATH_TYPE@115..116
+            PATH_REF@115..116
+              PATH_SEGMENT_REF@115..116
+                IDENT@115..116 "t"
+      WHITESPACE@116..117 "\n"
+      R_PAREN@117..118 ")"
+    SEMICOLON@118..119 ";"
+  WHITESPACE@119..121 "\n\n"
+  CREATE_AGGREGATE@121..231
+    CREATE_KW@121..127 "create"
+    WHITESPACE@127..128 " "
+    AGGREGATE_KW@128..137 "aggregate"
+    WHITESPACE@137..138 " "
+    AGGREGATE_NAME@138..160
+      PATH@138..160
+        PATH_SEGMENT@138..160
+          IDENT@138..160 "aggregate_with_default"
+    PARAM_LIST@160..185
+      L_PAREN@160..161 "("
+      PARAM@161..184
+        PARAM_NAME@161..166
+          VALUE_KW@161..166 "value"
+        WHITESPACE@166..167 " "
+        PATH_TYPE@167..174
+          PATH_REF@167..174
+            PATH_SEGMENT_REF@167..174
+              INTEGER_KW@167..174 "integer"
+        WHITESPACE@174..175 " "
+        PARAM_DEFAULT@175..184
+          DEFAULT_KW@175..182 "default"
+          WHITESPACE@182..183 " "
+          LITERAL@183..184
+            INT_NUMBER@183..184 "1"
+      R_PAREN@184..185 ")"
+    WHITESPACE@185..186 " "
+    ATTRIBUTE_LIST@186..230
+      L_PAREN@186..187 "("
+      WHITESPACE@187..190 "\n  "
+      ATTRIBUTE_OPTION@190..209
+        ATTRIBUTE_NAME@190..195
+          IDENT@190..195 "sfunc"
+        WHITESPACE@195..196 " "
+        EQ@196..197 "="
+        WHITESPACE@197..198 " "
+        ATTRIBUTE_VALUE@198..209
+          PATH_TYPE@198..209
+            PATH_REF@198..209
+              PATH_SEGMENT_REF@198..209
+                IDENT@198..209 "integer_sum"
+      COMMA@209..210 ","
+      WHITESPACE@210..213 "\n  "
+      ATTRIBUTE_OPTION@213..228
+        ATTRIBUTE_NAME@213..218
+          IDENT@213..218 "stype"
+        WHITESPACE@218..219 " "
+        EQ@219..220 "="
+        WHITESPACE@220..221 " "
+        ATTRIBUTE_VALUE@221..228
+          PATH_TYPE@221..228
+            PATH_REF@221..228
+              PATH_SEGMENT_REF@221..228
+                INTEGER_KW@221..228 "integer"
+      WHITESPACE@228..229 "\n"
+      R_PAREN@229..230 ")"
+    SEMICOLON@230..231 ";"
+  WHITESPACE@231..233 "\n\n"
+  CREATE_AGGREGATE@233..365
+    CREATE_KW@233..239 "create"
+    WHITESPACE@239..240 " "
+    AGGREGATE_KW@240..249 "aggregate"
+    WHITESPACE@249..250 " "
+    AGGREGATE_NAME@250..267
+      PATH@250..267
+        PATH_SEGMENT@250..267
+          IDENT@250..267 "ordered_aggregate"
+    PARAM_LIST@267..319
+      L_PAREN@267..268 "("
+      WHITESPACE@268..271 "\n  "
+      PARAM@271..285
+        PARAM_NAME@271..277
+          IDENT@271..277 "direct"
+        WHITESPACE@277..278 " "
+        PATH_TYPE@278..285
+          PATH_REF@278..285
+            PATH_SEGMENT_REF@278..285
+              INTEGER_KW@278..285 "integer"
+      WHITESPACE@285..286 " "
+      AGGREGATE_ORDER_BY@286..317
+        ORDER_KW@286..291 "order"
+        WHITESPACE@291..292 " "
+        BY_KW@292..294 "by"
+        WHITESPACE@294..295 " "
+        PARAM@295..317
+          PARAM_NAME@295..305
+            IDENT@295..305 "aggregated"
+          WHITESPACE@305..306 " "
+          PATH_TYPE@306..313
+            PATH_REF@306..313
+              PATH_SEGMENT_REF@306..313
+                INTEGER_KW@306..313 "integer"
+          WHITESPACE@313..314 " "
+          PARAM_DEFAULT@314..317
+            EQ@314..315 "="
+            WHITESPACE@315..316 " "
+            LITERAL@316..317
+              INT_NUMBER@316..317 "1"
+      WHITESPACE@317..318 "\n"
+      R_PAREN@318..319 ")"
+    WHITESPACE@319..320 " "
+    ATTRIBUTE_LIST@320..364
+      L_PAREN@320..321 "("
+      WHITESPACE@321..324 "\n  "
+      ATTRIBUTE_OPTION@324..343
+        ATTRIBUTE_NAME@324..329
+          IDENT@324..329 "sfunc"
+        WHITESPACE@329..330 " "
+        EQ@330..331 "="
+        WHITESPACE@331..332 " "
+        ATTRIBUTE_VALUE@332..343
+          PATH_TYPE@332..343
+            PATH_REF@332..343
+              PATH_SEGMENT_REF@332..343
+                IDENT@332..343 "integer_sum"
+      COMMA@343..344 ","
+      WHITESPACE@344..347 "\n  "
+      ATTRIBUTE_OPTION@347..362
+        ATTRIBUTE_NAME@347..352
+          IDENT@347..352 "stype"
+        WHITESPACE@352..353 " "
+        EQ@353..354 "="
+        WHITESPACE@354..355 " "
+        ATTRIBUTE_VALUE@355..362
+          PATH_TYPE@355..362
+            PATH_REF@355..362
+              PATH_SEGMENT_REF@355..362
+                INTEGER_KW@355..362 "integer"
+      WHITESPACE@362..363 "\n"
+      R_PAREN@363..364 ")"
+    SEMICOLON@364..365 ";"
+  WHITESPACE@365..366 "\n"
 
 error[syntax-error]: Out params are not allowed with aggregates.
   ╭▸ 
-2 │ alter aggregate a (in t, out u, inout v, in out w)
+2 │ create aggregate a(in x, out y, inout z, in out w) (
   ╰╴                         ━━━
 error[syntax-error]: In Out params are not allowed with aggregates.
   ╭▸ 
-2 │ alter aggregate a (in t, out u, inout v, in out w)
+2 │ create aggregate a(in x, out y, inout z, in out w) (
   ╰╴                                ━━━━━
 error[syntax-error]: In Out params are not allowed with aggregates.
   ╭▸ 
-2 │ alter aggregate a (in t, out u, inout v, in out w)
+2 │ create aggregate a(in x, out y, inout z, in out w) (
   ╰╴                                         ━━━━━━
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+7 │ create aggregate aggregate_with_default(value integer default 1) (
+  ╰╴                                                      ━━━━━━━━━
+error[syntax-error]: Defaults are not allowed.
+   ╭▸ 
+13 │   direct integer order by aggregated integer = 1
+   ╰╴                                             ━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_aggregate_params_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_aggregate_params_validation.snap
index 2a4c1183..654fdd5f 100644
--- a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_aggregate_params_validation.snap
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_aggregate_params_validation.snap
@@ -2,7 +2,7 @@
 source: crates/squawk_syntax/src/test.rs
 input_file: crates/squawk_syntax/test_data/validation/drop_aggregate_params.sql
 ---
-SOURCE_FILE@0..444
+SOURCE_FILE@0..488
   WHITESPACE@0..1 "\n"
   COMMENT@1..8 "-- full"
   WHITESPACE@8..9 "\n"
@@ -255,7 +255,35 @@ SOURCE_FILE@0..444
         WHITESPACE@439..440 "\n"
         R_PAREN@440..441 ")"
     SEMICOLON@441..442 ";"
-  WHITESPACE@442..444 "\n\n"
+  WHITESPACE@442..445 "\n\n\n"
+  DROP_AGGREGATE@445..487
+    DROP_KW@445..449 "drop"
+    WHITESPACE@449..450 " "
+    AGGREGATE_KW@450..459 "aggregate"
+    WHITESPACE@459..460 " "
+    AGGREGATE@460..486
+      PATH_REF@460..461
+        PATH_SEGMENT_REF@460..461
+          IDENT@460..461 "a"
+      PARAM_LIST@461..486
+        L_PAREN@461..462 "("
+        PARAM@462..485
+          PARAM_NAME@462..467
+            VALUE_KW@462..467 "value"
+          WHITESPACE@467..468 " "
+          PATH_TYPE@468..475
+            PATH_REF@468..475
+              PATH_SEGMENT_REF@468..475
+                INTEGER_KW@468..475 "integer"
+          WHITESPACE@475..476 " "
+          PARAM_DEFAULT@476..485
+            DEFAULT_KW@476..483 "default"
+            WHITESPACE@483..484 " "
+            LITERAL@484..485
+              INT_NUMBER@484..485 "1"
+        R_PAREN@485..486 ")"
+    SEMICOLON@486..487 ";"
+  WHITESPACE@487..488 "\n"
 
 error[syntax-error]: Out params are not allowed with aggregates.
   ╭▸ 
@@ -277,3 +305,7 @@ error[syntax-error]: Out params are not allowed with aggregates.
    ╭▸ 
 31 │     out b numeric,
    ╰╴    ━━━
+error[syntax-error]: Defaults are not allowed.
+   ╭▸ 
+36 │ drop aggregate a(value integer default 1);
+   ╰╴                               ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_function_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_function_validation.snap
new file mode 100644
index 00000000..9cbd2d0c
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_function_validation.snap
@@ -0,0 +1,40 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/drop_function.sql
+---
+SOURCE_FILE@0..42
+  DROP_FUNCTION@0..41
+    DROP_KW@0..4 "drop"
+    WHITESPACE@4..5 " "
+    FUNCTION_KW@5..13 "function"
+    WHITESPACE@13..14 " "
+    FUNCTION_SIG_LIST@14..40
+      FUNCTION_SIG@14..40
+        FUNCTION_NAME_REF@14..15
+          PATH_REF@14..15
+            PATH_SEGMENT_REF@14..15
+              IDENT@14..15 "f"
+        PARAM_LIST@15..40
+          L_PAREN@15..16 "("
+          PARAM@16..39
+            PARAM_NAME@16..21
+              VALUE_KW@16..21 "value"
+            WHITESPACE@21..22 " "
+            PATH_TYPE@22..29
+              PATH_REF@22..29
+                PATH_SEGMENT_REF@22..29
+                  INTEGER_KW@22..29 "integer"
+            WHITESPACE@29..30 " "
+            PARAM_DEFAULT@30..39
+              DEFAULT_KW@30..37 "default"
+              WHITESPACE@37..38 " "
+              LITERAL@38..39
+                INT_NUMBER@38..39 "1"
+          R_PAREN@39..40 ")"
+    SEMICOLON@40..41 ";"
+  WHITESPACE@41..42 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ drop function f(value integer default 1);
+  ╰╴                              ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_procedure_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_procedure_validation.snap
new file mode 100644
index 00000000..5bf371f2
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_procedure_validation.snap
@@ -0,0 +1,40 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/drop_procedure.sql
+---
+SOURCE_FILE@0..43
+  DROP_PROCEDURE@0..42
+    DROP_KW@0..4 "drop"
+    WHITESPACE@4..5 " "
+    PROCEDURE_KW@5..14 "procedure"
+    WHITESPACE@14..15 " "
+    PROCEDURE_SIG_LIST@15..41
+      PROCEDURE_SIG@15..41
+        PROCEDURE_NAME_REF@15..16
+          PATH_REF@15..16
+            PATH_SEGMENT_REF@15..16
+              IDENT@15..16 "p"
+        PARAM_LIST@16..41
+          L_PAREN@16..17 "("
+          PARAM@17..40
+            PARAM_NAME@17..22
+              VALUE_KW@17..22 "value"
+            WHITESPACE@22..23 " "
+            PATH_TYPE@23..30
+              PATH_REF@23..30
+                PATH_SEGMENT_REF@23..30
+                  INTEGER_KW@23..30 "integer"
+            WHITESPACE@30..31 " "
+            PARAM_DEFAULT@31..40
+              DEFAULT_KW@31..38 "default"
+              WHITESPACE@38..39 " "
+              LITERAL@39..40
+                INT_NUMBER@39..40 "1"
+          R_PAREN@40..41 ")"
+    SEMICOLON@41..42 ";"
+  WHITESPACE@42..43 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ drop procedure p(value integer default 1);
+  ╰╴                               ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_routine_validation.snap b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_routine_validation.snap
new file mode 100644
index 00000000..ec0b06be
--- /dev/null
+++ b/crates/squawk_syntax/src/snapshots/squawk_syntax__test__drop_routine_validation.snap
@@ -0,0 +1,40 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/drop_routine.sql
+---
+SOURCE_FILE@0..41
+  DROP_ROUTINE@0..40
+    DROP_KW@0..4 "drop"
+    WHITESPACE@4..5 " "
+    ROUTINE_KW@5..12 "routine"
+    WHITESPACE@12..13 " "
+    ROUTINE_SIG_LIST@13..39
+      ROUTINE_SIG@13..39
+        ROUTINE_NAME_REF@13..14
+          PATH_REF@13..14
+            PATH_SEGMENT_REF@13..14
+              IDENT@13..14 "r"
+        PARAM_LIST@14..39
+          L_PAREN@14..15 "("
+          PARAM@15..38
+            PARAM_NAME@15..20
+              VALUE_KW@15..20 "value"
+            WHITESPACE@20..21 " "
+            PATH_TYPE@21..28
+              PATH_REF@21..28
+                PATH_SEGMENT_REF@21..28
+                  INTEGER_KW@21..28 "integer"
+            WHITESPACE@28..29 " "
+            PARAM_DEFAULT@29..38
+              DEFAULT_KW@29..36 "default"
+              WHITESPACE@36..37 " "
+              LITERAL@37..38
+                INT_NUMBER@37..38 "1"
+          R_PAREN@38..39 ")"
+    SEMICOLON@39..40 ";"
+  WHITESPACE@40..41 "\n"
+
+error[syntax-error]: Defaults are not allowed.
+  ╭▸ 
+1 │ drop routine r(value integer default 1);
+  ╰╴                             ━━━━━━━━━
diff --git a/crates/squawk_syntax/src/validation.rs b/crates/squawk_syntax/src/validation.rs
index fce10927..74707ebf 100644
--- a/crates/squawk_syntax/src/validation.rs
+++ b/crates/squawk_syntax/src/validation.rs
@@ -29,10 +29,13 @@ pub(crate) fn validate(root: &SyntaxNode, errors: &mut Vec<SyntaxError>) {
                 ast::CustomOp(it) => validate_custom_op_length(it, errors),
                 ast::Do(it) => validate_do(it, errors),
                 ast::FuncOptionList(it) => validate_func_option_list(it, errors),
+                ast::FunctionSig(it) => validate_param_defaults(it.param_list(), errors),
                 ast::FromAlias(it) => validate_non_empty_column_list(it.columns(), errors),
                 ast::RetType(it) => validate_non_empty_column_list(it.return_table_arg_list(), errors),
                 ast::WithTable(it) => validate_non_empty_column_list(it.column_list(), errors),
                 ast::PrefixExpr(it) => validate_prefix_expr(it, errors),
+                ast::ProcedureSig(it) => validate_param_defaults(it.param_list(), errors),
+                ast::RoutineSig(it) => validate_param_defaults(it.param_list(), errors),
                 ast::ArrayExpr(it) => validate_array_expr(it, errors),
                 ast::JoinExpr(it) => validate_join_expr(it, errors),
                 ast::Literal(it) => validate_literal(it, errors),
@@ -895,7 +898,22 @@ fn validate_create_function(function: ast::CreateFunction, acc: &mut Vec<SyntaxE
     }
 }
 
+fn validate_param_defaults(params: Option<ast::ParamList>, acc: &mut Vec<SyntaxError>) {
+    let Some(params) = params else {
+        return;
+    };
+    for param in params.all_params() {
+        if let Some(default) = param.param_default() {
+            acc.push(SyntaxError::new(
+                "Defaults are not allowed.",
+                default.syntax().text_range(),
+            ));
+        }
+    }
+}
+
 fn validate_aggregate_params(aggregate_params: Option<ast::ParamList>, acc: &mut Vec<SyntaxError>) {
+    validate_param_defaults(aggregate_params.clone(), acc);
     if let Some(params) = aggregate_params {
         for p in params.all_params() {
             if let Some(mode) = p.mode() {
diff --git a/crates/squawk_syntax/test_data/validation/alter_aggregate_params.sql b/crates/squawk_syntax/test_data/validation/alter_aggregate_params.sql
index f82bde48..943d361c 100644
--- a/crates/squawk_syntax/test_data/validation/alter_aggregate_params.sql
+++ b/crates/squawk_syntax/test_data/validation/alter_aggregate_params.sql
@@ -1,5 +1,5 @@
 -- can't have out params in aggregates
-create aggregate a(in x, out y, inout z, in out w) (
-  sfunc = f,
-  stype = t
-);
+alter aggregate a (in t, out u, inout v, in out w)
+    set schema s;
+
+alter aggregate a(value integer default 1) rename to a2;
diff --git a/crates/squawk_syntax/test_data/validation/alter_function.sql b/crates/squawk_syntax/test_data/validation/alter_function.sql
new file mode 100644
index 00000000..596f94f8
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/alter_function.sql
@@ -0,0 +1 @@
+alter function f(value integer default 1) rename to f2;
diff --git a/crates/squawk_syntax/test_data/validation/alter_procedure.sql b/crates/squawk_syntax/test_data/validation/alter_procedure.sql
new file mode 100644
index 00000000..3d24e672
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/alter_procedure.sql
@@ -0,0 +1 @@
+alter procedure p(value integer default 1) rename to p2;
diff --git a/crates/squawk_syntax/test_data/validation/alter_routine.sql b/crates/squawk_syntax/test_data/validation/alter_routine.sql
new file mode 100644
index 00000000..3bb63948
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/alter_routine.sql
@@ -0,0 +1 @@
+alter routine r(value integer default 1) rename to r2;
diff --git a/crates/squawk_syntax/test_data/validation/comment.sql b/crates/squawk_syntax/test_data/validation/comment.sql
new file mode 100644
index 00000000..70e23773
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/comment.sql
@@ -0,0 +1,4 @@
+comment on function f(value integer default 1) is 'function';
+comment on procedure p(value integer default 1) is 'procedure';
+comment on routine r(value integer default 1) is 'routine';
+comment on aggregate a(value integer default 1) is 'aggregate';
diff --git a/crates/squawk_syntax/test_data/validation/create_aggregate_params.sql b/crates/squawk_syntax/test_data/validation/create_aggregate_params.sql
index 3dddde01..1a7aae45 100644
--- a/crates/squawk_syntax/test_data/validation/create_aggregate_params.sql
+++ b/crates/squawk_syntax/test_data/validation/create_aggregate_params.sql
@@ -1,4 +1,17 @@
 -- can't have out params in aggregates
-alter aggregate a (in t, out u, inout v, in out w)
-    set schema s;
+create aggregate a(in x, out y, inout z, in out w) (
+  sfunc = f,
+  stype = t
+);
 
+create aggregate aggregate_with_default(value integer default 1) (
+  sfunc = integer_sum,
+  stype = integer
+);
+
+create aggregate ordered_aggregate(
+  direct integer order by aggregated integer = 1
+) (
+  sfunc = integer_sum,
+  stype = integer
+);
diff --git a/crates/squawk_syntax/test_data/validation/drop_aggregate_params.sql b/crates/squawk_syntax/test_data/validation/drop_aggregate_params.sql
index 2e82890b..120aa6da 100644
--- a/crates/squawk_syntax/test_data/validation/drop_aggregate_params.sql
+++ b/crates/squawk_syntax/test_data/validation/drop_aggregate_params.sql
@@ -32,3 +32,5 @@ drop aggregate foo.bar(
     text
 );
 
+
+drop aggregate a(value integer default 1);
diff --git a/crates/squawk_syntax/test_data/validation/drop_function.sql b/crates/squawk_syntax/test_data/validation/drop_function.sql
new file mode 100644
index 00000000..a29541cc
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/drop_function.sql
@@ -0,0 +1 @@
+drop function f(value integer default 1);
diff --git a/crates/squawk_syntax/test_data/validation/drop_procedure.sql b/crates/squawk_syntax/test_data/validation/drop_procedure.sql
new file mode 100644
index 00000000..29422cf5
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/drop_procedure.sql
@@ -0,0 +1 @@
+drop procedure p(value integer default 1);
diff --git a/crates/squawk_syntax/test_data/validation/drop_routine.sql b/crates/squawk_syntax/test_data/validation/drop_routine.sql
new file mode 100644
index 00000000..1dfc6311
--- /dev/null
+++ b/crates/squawk_syntax/test_data/validation/drop_routine.sql
@@ -0,0 +1 @@
+drop routine r(value integer default 1);