sql: Support tuple column access and tuple stars

This work is yet another step towards cockroachdb#16971.

The labeled tuples introduced in cockroachdb#25283 can now be accessed using
their labels or using a star, e.g. `(E).*`.

Release note (sql change): Labeled tuples can now be accessed using
their labels (e.g. `SELECT (x).word FROM (SELECT pg_expand_keywords()
AS x)` or a star (e.g. `SELECT (x).* FROM (SELECT pg_expand_keywords()
AS x)`).

Co-authored-by: Raphael 'kena' Poss <knz@cockroachlabs.com>

pkg/sql/logictest/testdata/logic_test/builtin_function

@@ -1253,7 +1253,7 @@ SELECT OVERLAY(foo.* PLACING 'string' FROM 'string') FROM (VALUES (1)) AS foo(x)
 query error cannot use "nonexistent.\*" without a FROM clause
 SELECT nonexistent.* IS NOT TRUE
 
-query error unsupported comparison operator: <tuple{int}> IS DISTINCT FROM <bool>
+query error unsupported comparison operator: <tuple{int AS x}> IS DISTINCT FROM <bool>
 SELECT foo.* IS NOT TRUE FROM (VALUES (1)) AS foo(x)
 
 query T

pkg/sql/logictest/testdata/logic_test/select

@@ -182,7 +182,7 @@ query error no data source matches pattern: bar.kv.\*
 SELECT bar.kv.* FROM kv
 
 # Don't panic with invalid names (#8024)
-query error cannot subscript type tuple\{string, string\} because it is not an array
+query error cannot subscript type tuple\{string AS k, string AS v\} because it is not an array
 SELECT kv.*[1] FROM kv
 
 query T colnames

pkg/sql/logictest/testdata/logic_test/srfs

@@ -436,10 +436,10 @@ SELECT (('a')).x
 query error pq: unnest\(\): cannot determine type of empty array. Consider annotating with the desired type, for example ARRAY\[\]:::int\[\]
 SELECT (unnest(ARRAY[])).*
 
-query I colnames
+query error type int is not composite
 SELECT (unnest(ARRAY[]:::INT[])).*
-----
-unnest
+
+subtest multi_column
 
 query TI colnames
 SELECT (information_schema._pg_expandarray(ARRAY['c', 'b', 'a'])).*
@@ -465,7 +465,7 @@ n
 2
 3
 
-query error pq: could not identify column "other" in record data type
+query error pq: could not identify column "other" in tuple{string AS x, int AS n}
 SELECT (information_schema._pg_expandarray(ARRAY['c', 'b', 'a'])).other
 
 query T colnames
@@ -503,16 +503,28 @@ c 1
 b 2
 a 3
 
-subtest 24866
+query I colnames
+SELECT (i.keys).n FROM (SELECT information_schema._pg_expandarray(ARRAY[3,2,1]) AS keys) AS i
+----
+n
+1
+2
+3
 
-# TODO(bram): #24866
-# query I colnames
-# SELECT (i.keys).n FROM (SELECT information_schema._pg_expandarray(ARRAY[3,2,1]) AS keys) AS i;
-# ----
-# n
-# 3
-# 2
-# 1
+query II colnames
+SELECT (i.keys).* FROM (SELECT information_schema._pg_expandarray(ARRAY[3,2,1]) AS keys) AS i
+----
+x  n
+3  1
+2  2
+1  3
+
+query T
+SELECT ((i.keys).*, 123) FROM (SELECT information_schema._pg_expandarray(ARRAY[3,2,1]) AS keys) AS i
+----
+((3, 1),123)
+((2, 2),123)
+((1, 3),123)
 
 subtest generate_subscripts
 
@@ -778,8 +790,10 @@ SELECT information_schema._pg_expandarray(indkey) FROM pg_index ORDER BY x, n
 #     pg_index
 # ----
 
+subtest correlated_json_object_keys
+
 statement ok
-CREATE TABLE j(x INT, y JSON);
+CREATE TABLE j(x INT PRIMARY KEY, y JSON);
   INSERT INTO j VALUES
      (1, '{"a":123,"b":456}'),
      (2, '{"c":111,"d":222}')
@@ -792,26 +806,70 @@ SELECT x, y->>json_object_keys(y) FROM j
 2  111
 2  222
 
+subtest correlated_multi_column
 
-# The following needs some more tuple support to work. #24866
-# query TTI
-# SELECT   a.attname, a.atttypid, atttypmod
-#     FROM pg_catalog.pg_class ct
-#     JOIN pg_catalog.pg_attribute a ON (ct.oid = a.attrelid)
-#     JOIN pg_catalog.pg_namespace n ON (ct.relnamespace = n.oid)
-#     JOIN (
-#       SELECT i.indexrelid, i.indrelid, i.indisprimary,
-#              information_schema._pg_expandarray(i.indkey) AS keys
-#         FROM pg_catalog.pg_index i
-#         ) i ON (a.attnum = (i.keys).x AND a.attrelid = i.indrelid)
-#    WHERE true
-#      AND n.nspname = 'information_schema'
-#      AND ct.relname = 'columns'
-#      AND i.indisprimary
-# ORDER BY a.attnum
-# ----
+query I colnames
+SELECT (i.keys).n FROM (SELECT information_schema._pg_expandarray(indkey) AS keys FROM pg_index) AS i
+----
+n
+1
+1
+1
+1
+2
+1
 
-# Ditto #24866
+subtest dbviz_example_query
+
+# DbVisualizer query from #24649 listed in #16971.
+query TTI
+SELECT   a.attname, a.atttypid, atttypmod
+    FROM pg_catalog.pg_class ct
+    JOIN pg_catalog.pg_attribute a ON (ct.oid = a.attrelid)
+    JOIN pg_catalog.pg_namespace n ON (ct.relnamespace = n.oid)
+    JOIN (
+      SELECT i.indexrelid, i.indrelid, i.indisprimary,
+             information_schema._pg_expandarray(i.indkey) AS keys
+        FROM pg_catalog.pg_index i
+        ) i ON (a.attnum = (i.keys).x AND a.attrelid = i.indrelid)
+   WHERE true
+     AND n.nspname = 'public'
+     AND ct.relname = 'j'
+     AND i.indisprimary
+ORDER BY a.attnum
+----
+x  20  -1
+
+subtest metabase_confluent_example_query
+
+# Test from metabase listed on #16971.
+# Also Kafka Confluent sink query from #25854.
+query TTTTIT
+SELECT NULL AS TABLE_CAT,
+       n.nspname AS TABLE_SCHEM,
+       ct.relname AS TABLE_NAME,
+       a.attname AS COLUMN_NAME,
+       (i.keys).n AS KEY_SEQ,
+       ci.relname AS PK_NAME
+    FROM pg_catalog.pg_class ct
+    JOIN pg_catalog.pg_attribute a ON (ct.oid = a.attrelid)
+    JOIN pg_catalog.pg_namespace n ON (ct.relnamespace = n.oid)
+    JOIN (SELECT i.indexrelid,
+                 i.indrelid,
+             i.indisprimary,
+             information_schema._pg_expandarray(i.indkey) AS keys
+        FROM pg_catalog.pg_index i) i ON (a.attnum = (i.keys).x AND a.attrelid = i.indrelid)
+    JOIN pg_catalog.pg_class ci ON (ci.oid = i.indexrelid)
+   WHERE true AND ct.relname = 'j' AND i.indisprimary
+ORDER BY table_name, pk_name, key_seq
+----
+NULL  public  j  x  1  primary
+
+subtest liquibase_example_query
+
+# # Test from #24713 (Liquibase) listed on #16971.
+# # TODO(knz) Needs support for pg_get_indexdef with 3 arguments,
+# # see #26629.
 # query TTTBTTIITTTTT
 # SELECT NULL AS table_cat,
 #        n.nspname AS table_schem,
@@ -856,7 +914,7 @@ SELECT x, y->>json_object_keys(y) FROM j
 # JOIN pg_catalog.pg_am am ON (ci.relam = am.oid)
 # WHERE TRUE
 #   AND n.nspname = 'public'
-#   AND ct.relname = 'act_de_databasechangelog'
+#   AND ct.relname = 'j'
 # ORDER BY non_unique,
 #          TYPE,
 #          index_name,

pkg/sql/logictest/testdata/logic_test/tuple

@@ -679,6 +679,8 @@ SELECT (((ROW(pow(1, 10.0) + 9) AS t1), 'a' || 'b') AS t2, t3) = (((ROW(sqrt(100
 a     b
 true  true
 
+subtest labeled_tuple_errors
+
 query error pq: tuples \(\(\(\(1, 2\) AS a, b\), 'equal'\) AS c, d\), \(\(\(\(1, 'huh'\) AS e, f\), 'equal'\) AS g, h\) are not comparable at index 1: tuples \(\(1, 2\) AS a, b\), \(\(1, 'huh'\) AS e, f\) are not comparable at index 2: unsupported comparison operator: <int> = <string>
 SELECT ((((1, 2) AS a, b), 'equal') AS c, d) = ((((1, 'huh') AS e, f), 'equal') AS g, h)
 
@@ -709,10 +711,14 @@ SELECT ((((((1, '2', 3) AS a, b, c), ((4,'5') AS a, b), (ROW(6) AS a)) AS a, b,
 r
 (((1, '2', 3), (4, '5'), (6)),(7, 8),('9'))
 
-### Accessing a specific column
+subtest labeled_tuple_column_access
 
 ## base working case
 
+# Accessing a specific column
+query error pq: could not identify column "x" in tuple{int AS a, int AS b, int AS c}
+SELECT (((1,2,3) AS a,b,c)).x
+
 query ITBITB colnames
 SELECT (((1,'2',true) AS a,b,c)).a
       ,(((1,'2',true) AS a,b,c)).b
@@ -724,7 +730,7 @@ SELECT (((1,'2',true) AS a,b,c)).a
 a  b  c     a  b  c
 1  2  true  1  2  true
 
-## A collection of error cases
+subtest labeled_tuple_column_access_errors
 
 # column doesn't exist
 query error pq: could not identify column "x" in tuple{int AS a, int AS b, int AS c}
@@ -744,33 +750,83 @@ SELECT ((1,2,3)).x
 query error pq: type tuple{int, int, int} is not composite
 SELECT ((1,2,3)).*
 
-# Non unique labels
-query error pq: found duplicate tuple label: "a"
-SELECT (((1,'2',true) AS a,b,a)).a
-
-## The following are all cases that will be addressed in future work
-
 # Accessing all the columns
-query error pq: star expansion of tuples is not supported
+
+query ITB colnames
 SELECT (((1,'2',true) AS a,b,c)).*
+----
+a  b  c
+1  2  true
 
-query error pq: star expansion of tuples is not supported
+query ITB colnames
 SELECT ((ROW(1,'2',true) AS a,b,c)).*
+----
+a  b  c
+1  2  true
+
+query T
+SELECT (((ROW(1,'2',true) AS a,b,c)).*, 456)
+----
+((1, '2', true),456)
+
+query I colnames
+SELECT ((ROW(1) AS a)).*
+----
+a
+1
+
 
-# From a Subquery
-query error pq: unimplemented: cannot access column "e" in non-tuple expression
-SELECT ((t)).e, ((t)).f, ((t)).g
+subtest literal_labeled_tuple_in_subquery
+
+query ITB colnames
+SELECT (x).e, (x).f, (x).g
+FROM (
+  SELECT ((1,'2',true) AS e,f,g) AS x
+)
+----
+e  f  g
+1  2  true
+
+query ITB colnames
+SELECT (x).*
 FROM (
-  SELECT ((1,'2',true) AS e,f,g) AS t
+  SELECT ((1,'2',true) AS e,f,g) AS x
 )
+----
+e  f  g
+1  2  true
+
+subtest labeled_tuples_derived_from_relational_subquery_schema
+
+# Needed until #26627 is resolved.
+statement ok
+set distsql=off
+
+query IT
+  SELECT (x).a, (x).b
+    FROM (SELECT (ROW(a, b) AS a, b) AS x FROM (VALUES (1, 'one')) AS t(a, b))
+----
+1 one
 
-# From a table directly
 statement ok
 CREATE TABLE t (a int, b string)
 
 statement ok
 INSERT INTO t VALUES (1, 'one'), (2, 'two')
 
+query IT
+  SELECT (x).a, (x).b
+    FROM (SELECT (ROW(a, b) AS a, b) AS x FROM t)
+ORDER BY 1
+   LIMIT 1
+----
+1 one
+
+statement ok
+set distsql=auto
+
+subtest labeled_column_access_from_table
+
 query error pq: column "t" does not exist
 SELECT (t).a FROM t
 

pkg/sql/opt/exec/execbuilder/testdata/aggregate

@@ -171,18 +171,18 @@ group      ·            ·           (count int, sum decimal, max int)  ·
 query TTTTT
 EXPLAIN (VERBOSE) SELECT count(DISTINCT a.*) FROM kv a, kv b
 ----
-group                ·            ·                             (count)                                                       ·
- │                   aggregate 0  count(DISTINCT (k, v, w, s))  ·                                                             ·
- └── render          ·            ·                             ("(k, v, w, s)")                                              ·
-      │              render 0     (a.k, a.v, a.w, a.s)          ·                                                             ·
-      └── join       ·            ·                             (k, v, w, s, k[omitted], v[omitted], w[omitted], s[omitted])  ·
-           │         type         cross                         ·                                                             ·
-           ├── scan  ·            ·                             (k, v, w, s)                                                  k!=NULL; key(k)
-           │         table        kv@primary                    ·                                                             ·
-           │         spans        ALL                           ·                                                             ·
-           └── scan  ·            ·                             (k[omitted], v[omitted], w[omitted], s[omitted])              k!=NULL; key(k)
-·                    table        kv@primary                    ·                                                             ·
-·                    spans        ALL                           ·                                                             ·
+group                ·            ·                                             (count)                                                       ·
+ │                   aggregate 0  count(DISTINCT ((k, v, w, s) AS k, v, w, s))  ·                                                             ·
+ └── render          ·            ·                                             ("((k, v, w, s) AS k, v, w, s)")                              ·
+      │              render 0     ((a.k, a.v, a.w, a.s) AS k, v, w, s)          ·                                                             ·
+      └── join       ·            ·                                             (k, v, w, s, k[omitted], v[omitted], w[omitted], s[omitted])  ·
+           │         type         cross                                         ·                                                             ·
+           ├── scan  ·            ·                                             (k, v, w, s)                                                  k!=NULL; key(k)
+           │         table        kv@primary                                    ·                                                             ·
+           │         spans        ALL                                           ·                                                             ·
+           └── scan  ·            ·                                             (k[omitted], v[omitted], w[omitted], s[omitted])              k!=NULL; key(k)
+·                    table        kv@primary                                    ·                                                             ·
+·                    spans        ALL                                           ·                                                             ·
 
 query TTT
 SELECT "Tree", "Field", "Description" FROM [

pkg/sql/opt/optbuilder/project.go

@@ -79,18 +79,18 @@ func (b *Builder) buildProjectionList(selects tree.SelectExprs, inScope *scope,
 			panic(builderError{err})
 		}
 
-		// Special handling for "*" and "<table>.*".
+		// Special handling for "*", "<table>.*" and "(E).*".
 		if v, ok := e.Expr.(tree.VarName); ok {
 			switch v.(type) {
-			case tree.UnqualifiedStar, *tree.AllColumnsSelector:
+			case tree.UnqualifiedStar, *tree.AllColumnsSelector, *tree.TupleStar:
 				if e.As != "" {
 					panic(builderError{pgerror.NewErrorf(pgerror.CodeSyntaxError,
 						"%q cannot be aliased", tree.ErrString(v))})
 				}
 
-				exprs := b.expandStar(e.Expr, inScope)
-				for _, e := range exprs {
-					b.buildScalarProjection(e, "", inScope, outScope)
+				labels, exprs := b.expandStar(e.Expr, inScope)
+				for i, e := range exprs {
+					b.buildScalarProjection(e, labels[i], inScope, outScope)
 				}
 				continue
 			}