settings: Add syntax for cluster settings

docs/generated/sql/bnf/BUILD.bazel

@@ -38,6 +38,7 @@ FILES = [
     "alter_table_partition_by",
     "alter_table_set_schema_stmt",
     "alter_table_stmt",
+    "alter_tenant_csetting_stmt",
     "alter_type",
     "alter_view",
     "alter_view_owner_stmt",

docs/generated/sql/bnf/alter_stmt.bnf

@@ -1,3 +1,4 @@
 alter_stmt ::=
 	alter_ddl_stmt
 	| alter_role_stmt
+	| alter_tenant_csetting_stmt

docs/generated/sql/bnf/alter_tenant_csetting_stmt.bnf

@@ -0,0 +1,5 @@
+alter_tenant_csetting_stmt ::=
+	'ALTER' 'TENANT' iconst64 'SET' 'CLUSTER' 'SETTING' var_name to_or_eq var_value
+	| 'ALTER' 'TENANT' 'ALL' 'SET' 'CLUSTER' 'SETTING' var_name to_or_eq var_value
+	| 'ALTER' 'TENANT' iconst64 'RESET' 'CLUSTER' 'SETTING' var_name
+	| 'ALTER' 'TENANT' 'ALL' 'RESET' 'CLUSTER' 'SETTING' var_name

docs/generated/sql/bnf/show_cluster_setting.bnf

@@ -4,3 +4,7 @@ show_csettings_stmt ::=
 	| 'SHOW' 'ALL' 'CLUSTER' 'SETTINGS'
 	| 'SHOW' 'CLUSTER' 'SETTINGS'
 	| 'SHOW' 'PUBLIC' 'CLUSTER' 'SETTINGS'
+	| 'SHOW' 'CLUSTER' 'SETTING' var_name 'FOR' 'TENANT' iconst64
+	| 'SHOW' 'ALL' 'CLUSTER' 'SETTINGS' 'FOR' 'TENANT' iconst64
+	| 'SHOW' 'CLUSTER' 'SETTINGS' 'FOR' 'TENANT' iconst64
+	| 'SHOW' 'PUBLIC' 'CLUSTER' 'SETTINGS' 'FOR' 'TENANT' iconst64

docs/generated/sql/bnf/stmt_block.bnf

@@ -135,6 +135,7 @@ fetch_cursor_stmt ::=
 alter_stmt ::=
 	alter_ddl_stmt
 	| alter_role_stmt
+	| alter_tenant_csetting_stmt
 
 backup_stmt ::=
 	'BACKUP' opt_backup_targets 'INTO' sconst_or_placeholder 'IN' string_or_placeholder_opt_list opt_as_of_clause opt_with_backup_options
@@ -456,6 +457,12 @@ alter_role_stmt ::=
 	| 'ALTER' 'ROLE_ALL' 'ALL' opt_in_database set_or_reset_clause
 	| 'ALTER' 'USER_ALL' 'ALL' opt_in_database set_or_reset_clause
 
+alter_tenant_csetting_stmt ::=
+	'ALTER' 'TENANT' iconst64 'SET' 'CLUSTER' 'SETTING' var_name to_or_eq var_value
+	| 'ALTER' 'TENANT' 'ALL' 'SET' 'CLUSTER' 'SETTING' var_name to_or_eq var_value
+	| 'ALTER' 'TENANT' iconst64 'RESET' 'CLUSTER' 'SETTING' var_name
+	| 'ALTER' 'TENANT' 'ALL' 'RESET' 'CLUSTER' 'SETTING' var_name
+
 opt_backup_targets ::=
 	targets
 
@@ -715,6 +722,10 @@ show_csettings_stmt ::=
 	| 'SHOW' 'ALL' 'CLUSTER' 'SETTINGS'
 	| 'SHOW' 'CLUSTER' 'SETTINGS'
 	| 'SHOW' 'PUBLIC' 'CLUSTER' 'SETTINGS'
+	| 'SHOW' 'CLUSTER' 'SETTING' var_name 'FOR' 'TENANT' iconst64
+	| 'SHOW' 'ALL' 'CLUSTER' 'SETTINGS' 'FOR' 'TENANT' iconst64
+	| 'SHOW' 'CLUSTER' 'SETTINGS' 'FOR' 'TENANT' iconst64
+	| 'SHOW' 'PUBLIC' 'CLUSTER' 'SETTINGS' 'FOR' 'TENANT' iconst64
 
 show_databases_stmt ::=
 	'SHOW' 'DATABASES' with_comment
@@ -1501,6 +1512,18 @@ set_or_reset_clause ::=
 	| 'RESET_ALL' 'ALL'
 	| 'RESET' session_var
 
+var_name ::=
+	name
+	| name attrs
+
+to_or_eq ::=
+	'='
+	| 'TO'
+
+var_value ::=
+	a_expr
+	| extra_var_value
+
 as_of_clause ::=
 	'AS' 'OF' 'SYSTEM' 'TIME' a_expr
 
@@ -1671,10 +1694,6 @@ session_var ::=
 	| 'LC_CTYPE'
 	| 'TIME' 'ZONE'
 
-var_name ::=
-	name
-	| name attrs
-
 restore_options_list ::=
 	( restore_options ) ( ( ',' restore_options ) )*
 
@@ -1716,14 +1735,6 @@ set_rest_more ::=
 set_rest ::=
 	generic_set
 
-to_or_eq ::=
-	'='
-	| 'TO'
-
-var_value ::=
-	a_expr
-	| extra_var_value
-
 with_comment ::=
 	'WITH' 'COMMENT'
 	| 
@@ -1991,6 +2002,13 @@ alter_backup_cmds ::=
 role_options ::=
 	( role_option ) ( ( role_option ) )*
 
+attrs ::=
+	( '.' unrestricted_name ) ( ( '.' unrestricted_name ) )*
+
+extra_var_value ::=
+	'ON'
+	| cockroachdb_extra_reserved_keyword
+
 backup_options ::=
 	'ENCRYPTION_PASSPHRASE' '=' string_or_placeholder
 	| 'REVISION_HISTORY'
@@ -2225,9 +2243,6 @@ column_name ::=
 session_var_parts ::=
 	( '.' 'identifier' ) ( ( '.' 'identifier' ) )*
 
-attrs ::=
-	( '.' unrestricted_name ) ( ( '.' unrestricted_name ) )*
-
 restore_options ::=
 	'ENCRYPTION_PASSPHRASE' '=' string_or_placeholder
 	| 'KMS' '=' string_or_placeholder_opt_list
@@ -2272,10 +2287,6 @@ offset_clause ::=
 generic_set ::=
 	var_name to_or_eq var_list
 
-extra_var_value ::=
-	'ON'
-	| cockroachdb_extra_reserved_keyword
-
 targets_roles ::=
 	'ROLE' role_spec_list
 	| 'SCHEMA' schema_name_list

pkg/gen/docs.bzl

@@ -50,6 +50,7 @@ DOCS_SRCS = [
   "//docs/generated/sql/bnf:alter_table_partition_by.bnf",
   "//docs/generated/sql/bnf:alter_table_set_schema_stmt.bnf",
   "//docs/generated/sql/bnf:alter_table_stmt.bnf",
+  "//docs/generated/sql/bnf:alter_tenant_csetting_stmt.bnf",
   "//docs/generated/sql/bnf:alter_type.bnf",
   "//docs/generated/sql/bnf:alter_view.bnf",
   "//docs/generated/sql/bnf:alter_view_owner_stmt.bnf",

pkg/sql/BUILD.bazel

@@ -18,6 +18,7 @@ go_library(
         "alter_table_locality.go",
         "alter_table_owner.go",
         "alter_table_set_schema.go",
+        "alter_tenant.go",
         "alter_type.go",
         "analyze_expr.go",
         "apply_join.go",

pkg/sql/alter_tenant.go

@@ -0,0 +1,90 @@
+// Copyright 2022 The Cockroach Authors.
+//
+// Use of this software is governed by the Business Source License
+// included in the file licenses/BSL.txt.
+//
+// As of the Change Date specified in that file, in accordance with
+// the Business Source License, use of this software will be governed
+// by the Apache License, Version 2.0, included in the file
+// licenses/APL.txt.
+
+package sql
+
+import (
+	"context"
+	"strings"
+
+	"github.com/cockroachdb/cockroach/pkg/roachpb"
+	"github.com/cockroachdb/cockroach/pkg/settings"
+	"github.com/cockroachdb/cockroach/pkg/settings/cluster"
+	"github.com/cockroachdb/cockroach/pkg/sql/pgwire/pgcode"
+	"github.com/cockroachdb/cockroach/pkg/sql/pgwire/pgerror"
+	"github.com/cockroachdb/cockroach/pkg/sql/sem/tree"
+	"github.com/cockroachdb/cockroach/pkg/util/errorutil/unimplemented"
+	"github.com/cockroachdb/errors"
+)
+
+// alterTenantSetClusterSettingNode represents an
+// ALTER TENANT ... SET CLUSTER SETTING statement.
+type alterTenantSetClusterSettingNode struct {
+	name      string
+	tenantID  roachpb.TenantID
+	tenantAll bool
+	st        *cluster.Settings
+	setting   settings.NonMaskedSetting
+	// If value is nil, the setting should be reset.
+	value tree.TypedExpr
+}
+
+// AlterTenantSetClusterSetting sets tenant level session variables.
+// Privileges: super user.
+func (p *planner) AlterTenantSetClusterSetting(
+	ctx context.Context, n *tree.AlterTenantSetClusterSetting,
+) (planNode, error) {
+	name := strings.ToLower(n.Name)
+	st := p.EvalContext().Settings
+	v, ok := settings.Lookup(name, settings.LookupForLocalAccess, p.ExecCfg().Codec.ForSystemTenant())
+	if !ok {
+		return nil, errors.Errorf("unknown cluster setting '%s'", name)
+	}
+
+	if err := checkPrivilegesForSetting(ctx, p, name, "set"); err != nil {
+		return nil, err
+	}
+
+	setting, ok := v.(settings.NonMaskedSetting)
+	if !ok {
+		return nil, errors.AssertionFailedf("expected writable setting, got %T", v)
+	}
+
+	// Error out if we're trying to call this from a non-system tenant or if
+	// we're trying to set a system-only variable.
+	if !p.execCfg.Codec.ForSystemTenant() {
+		return nil, pgerror.Newf(pgcode.InsufficientPrivilege,
+			"ALTER TENANT can only be called by system operators")
+	}
+	if setting.Class() == settings.SystemOnly {
+		return nil, pgerror.Newf(pgcode.InsufficientPrivilege,
+			"%s is a system-only setting and must be set at the host cluster level using SET CLUSTER SETTING", name)
+	}
+
+	value, err := p.getAndValidateTypedClusterSetting(ctx, name, n.Value, setting)
+	if err != nil {
+		return nil, err
+	}
+
+	node := alterTenantSetClusterSettingNode{
+		name: name, tenantID: n.TenantID, tenantAll: n.TenantAll, st: st,
+		setting: setting, value: value,
+	}
+	return &node, nil
+}
+
+func (n *alterTenantSetClusterSettingNode) startExec(params runParams) error {
+	return unimplemented.NewWithIssue(73857,
+		`unimplemented: tenant-level cluster settings not supported`)
+}
+
+func (n *alterTenantSetClusterSettingNode) Next(_ runParams) (bool, error) { return false, nil }
+func (n *alterTenantSetClusterSettingNode) Values() tree.Datums            { return nil }
+func (n *alterTenantSetClusterSettingNode) Close(_ context.Context)        {}

pkg/sql/delegate/show_all_cluster_settings.go

@@ -15,6 +15,7 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/sql/pgwire/pgerror"
 	"github.com/cockroachdb/cockroach/pkg/sql/roleoption"
 	"github.com/cockroachdb/cockroach/pkg/sql/sem/tree"
+	"github.com/cockroachdb/cockroach/pkg/util/errorutil/unimplemented"
 )
 
 func (d *delegator) delegateShowClusterSettingList(
@@ -24,6 +25,10 @@ func (d *delegator) delegateShowClusterSettingList(
 	if err != nil {
 		return nil, err
 	}
+	if stmt.TenantID.IsSet() {
+		return nil, unimplemented.NewWithIssue(73857,
+			`unimplemented: tenant-level cluster settings not supported`)
+	}
 	hasModify, err := d.catalog.HasRoleOption(d.ctx, roleoption.MODIFYCLUSTERSETTING)
 	if err != nil {
 		return nil, err

pkg/sql/logictest/testdata/logic_test/cluster_settings

@@ -22,6 +22,9 @@ SET CLUSTER SETTING sql.conn.max_read_buffer_message_size = '1b'
 statement ok
 SET CLUSTER SETTING sql.conn.max_read_buffer_message_size = '64MB'
 
+statement ok
+RESET CLUSTER SETTING sql.conn.max_read_buffer_message_size
+
 # Test permissions for modifying cluster settings.
 
 user testuser
@@ -162,3 +165,53 @@ SET CLUSTER SETTING kv.snapshot_rebalance.max_rate = '10Mib'
 onlyif config 3node-tenant
 statement error unknown setting
 SHOW CLUSTER SETTING kv.snapshot_rebalance.max_rate
+
+# Test a cluster setting which is SystemOnly
+subtest tenant-cluster-settings
+
+# Skip this test when inside a tenant, as this setting won't be visible in
+# there.
+skipif config 3node-tenant
+statement error admission.kv.enabled is a system-only setting and must be set at the host cluster level using SET CLUSTER SETTING
+ALTER TENANT 10 SET CLUSTER SETTING admission.kv.enabled=true
+
+onlyif config 3node-tenant
+statement error ALTER TENANT can only be called by system operators
+ALTER TENANT 10 SET CLUSTER SETTING server.mem_profile.total_dump_size_limit='10M'
+
+skipif config 3node-tenant
+statement error unimplemented
+ALTER TENANT 10 SET CLUSTER SETTING server.mem_profile.total_dump_size_limit='10M'
+
+skipif config 3node-tenant
+statement error unimplemented
+ALTER TENANT ALL SET CLUSTER SETTING server.mem_profile.total_dump_size_limit='10M'
+
+skipif config 3node-tenant
+statement error unimplemented
+ALTER TENANT 10 RESET CLUSTER SETTING server.mem_profile.total_dump_size_limit
+
+skipif config 3node-tenant
+statement error unimplemented
+ALTER TENANT ALL RESET CLUSTER SETTING server.mem_profile.total_dump_size_limit
+
+skipif config 3node-tenant
+statement error pq: at or near "EOF": syntax error: invalid tenant ID
+ALTER TENANT 0 SET CLUSTER SETTING server.mem_profile.total_dump_size_limit='10M'
+
+skipif config 3node-tenant
+statement error pq: at or near "EOF": syntax error: invalid tenant ID
+ALTER TENANT 0 RESET CLUSTER SETTING server.mem_profile.total_dump_size_limit
+
+statement error unimplemented
+SHOW CLUSTER SETTING server.mem_profile.total_dump_size_limit FOR TENANT 10
+
+statement error unimplemented
+SHOW CLUSTER SETTINGS FOR TENANT 10
+
+statement error unimplemented
+SHOW PUBLIC CLUSTER SETTINGS FOR TENANT 10
+
+statement error unimplemented
+SHOW ALL CLUSTER SETTINGS FOR TENANT 10
+

pkg/sql/opaque.go

@@ -105,6 +105,8 @@ func planOpaque(ctx context.Context, p *planner, stmt tree.Statement) (planNode,
 		return p.AlterTableOwner(ctx, n)
 	case *tree.AlterTableSetSchema:
 		return p.AlterTableSetSchema(ctx, n)
+	case *tree.AlterTenantSetClusterSetting:
+		return p.AlterTenantSetClusterSetting(ctx, n)
 	case *tree.AlterType:
 		return p.AlterType(ctx, n)
 	case *tree.AlterRole:
@@ -251,6 +253,7 @@ func init() {
 		&tree.AlterTableLocality{},
 		&tree.AlterTableOwner{},
 		&tree.AlterTableSetSchema{},
+		&tree.AlterTenantSetClusterSetting{},
 		&tree.AlterType{},
 		&tree.AlterSequence{},
 		&tree.AlterRole{},

pkg/sql/parser/help_test.go

@@ -50,6 +50,11 @@ func TestContextualHelp(t *testing.T) {
 		{`ALTER TABLE blah RENAME TO blih ??`, `ALTER TABLE`},
 		{`ALTER TABLE blah SPLIT AT (SELECT 1) ??`, `ALTER TABLE`},
 
+		{`ALTER TENANT 1 SET CLUSTER SETTING ???`, `ALTER TENANT`},
+		{`ALTER TENANT 1 RESET CLUSTER SETTING ???`, `ALTER TENANT`},
+		{`ALTER TENANT ALL SET CLUSTER SETTING ???`, `ALTER TENANT`},
+		{`ALTER TENANT ALL RESET CLUSTER SETTING ???`, `ALTER TENANT`},
+
 		{`ALTER TYPE ??`, `ALTER TYPE`},
 		{`ALTER TYPE t ??`, `ALTER TYPE`},
 		{`ALTER TYPE t ADD VALUE ??`, `ALTER TYPE`},
@@ -327,6 +332,10 @@ func TestContextualHelp(t *testing.T) {
 
 		{`SHOW CLUSTER SETTING all ??`, `SHOW CLUSTER SETTING`},
 		{`SHOW ALL CLUSTER ??`, `SHOW CLUSTER SETTING`},
+		{`SHOW CLUSTER SETTING a FOR TENANT ??`, `SHOW CLUSTER SETTING`},
+		{`SHOW ALL CLUSTER SETTINGS FOR TENANT ??`, `SHOW CLUSTER SETTING`},
+		{`SHOW CLUSTER SETTINGS FOR TENANT ??`, `SHOW CLUSTER SETTING`},
+		{`SHOW PUBLIC CLUSTER SETTINGS FOR TENANT ??`, `SHOW CLUSTER SETTING`},
 
 		{`SHOW COLUMNS FROM ??`, `SHOW COLUMNS`},
 		{`SHOW COLUMNS FROM foo ??`, `SHOW COLUMNS`},