Merge #71915

71915: sql: implement custom session options r=rafiss a=otan

Resolves #70033

See individual commit for details. I've left out memory accounting for now.

Co-authored-by: Oliver Tan <[email protected]>

docs/generated/sql/bnf/stmt_block.bnf

@@ -1556,6 +1556,7 @@ insert_column_item ::=
 
 session_var ::=
 	'identifier'
+	| 'identifier' session_var_parts
 	| 'ALL'
 	| 'DATABASE'
 	| 'NAMES'
@@ -2118,6 +2119,9 @@ like_table_option_list ::=
 column_name ::=
 	name
 
+session_var_parts ::=
+	( '.' 'identifier' ) ( ( '.' 'identifier' ) )*
+
 attrs ::=
 	( '.' unrestricted_name ) ( ( '.' unrestricted_name ) )*
 

pkg/sql/BUILD.bazel

@@ -195,6 +195,7 @@ go_library(
         "show_stats.go",
         "show_trace.go",
         "show_trace_replica.go",
+        "show_var.go",
         "show_zone_config.go",
         "sort.go",
         "split.go",

pkg/sql/conn_executor.go

@@ -684,8 +684,12 @@ func (s *Server) newSessionData(args SessionArgs) *sessiondata.SessionData {
 		LocalOnlySessionData: sessiondatapb.LocalOnlySessionData{
 			ResultsBufferSize: args.ConnResultsBufferSize,
 			IsSuperuser:       args.IsSuperuser,
+			CustomOptions:     make(map[string]string),
 		},
 	}
+	for k, v := range args.CustomOptionSessionDefaults {
+		sd.CustomOptions[k] = v
+	}
 	s.populateMinimalSessionData(sd)
 	return sd
 }

pkg/sql/crdb_internal.go

@@ -1452,7 +1452,10 @@ CREATE TABLE crdb_internal.session_variables (
 	populate: func(ctx context.Context, p *planner, _ catalog.DatabaseDescriptor, addRow func(...tree.Datum) error) error {
 		for _, vName := range varNames {
 			gen := varGen[vName]
-			value := gen.Get(&p.extendedEvalCtx)
+			value, err := gen.Get(&p.extendedEvalCtx)
+			if err != nil {
+				return err
+			}
 			if err := addRow(
 				tree.NewDString(vName),
 				tree.NewDString(value),

pkg/sql/delegate/show_var.go

@@ -41,6 +41,10 @@ func (d *delegator) delegateShowVar(n *tree.ShowVar) (tree.Statement, error) {
 	}
 
 	if _, ok := ValidVars[name]; !ok {
+		// Custom options go to planNode.
+		if strings.Contains(name, ".") {
+			return nil, nil
+		}
 		return nil, pgerror.Newf(pgcode.UndefinedObject,
 			"unrecognized configuration parameter %q", origName)
 	}

pkg/sql/exec_util.go

@@ -1750,9 +1750,10 @@ type SessionDefaults map[string]string
 
 // SessionArgs contains arguments for serving a client connection.
 type SessionArgs struct {
-	User            security.SQLUsername
-	IsSuperuser     bool
-	SessionDefaults SessionDefaults
+	User                        security.SQLUsername
+	IsSuperuser                 bool
+	SessionDefaults             SessionDefaults
+	CustomOptionSessionDefaults SessionDefaults
 	// RemoteAddr is the client's address. This is nil iff this is an internal
 	// client.
 	RemoteAddr            net.Addr
@@ -2807,6 +2808,13 @@ func (m *sessionDataMutator) SetLocation(loc *time.Location) {
 	m.bufferParamStatusUpdate("TimeZone", sessionDataTimeZoneFormat(loc))
 }
 
+func (m *sessionDataMutator) SetCustomOption(name, val string) {
+	if m.data.CustomOptions == nil {
+		m.data.CustomOptions = make(map[string]string)
+	}
+	m.data.CustomOptions[name] = val
+}
+
 func (m *sessionDataMutator) SetReadOnly(val bool) {
 	// The read-only state is special; it's set as a session variable (SET
 	// transaction_read_only=<>), but it represents per-txn state, not

pkg/sql/information_schema.go

@@ -1528,7 +1528,10 @@ var informationSchemaSessionVariables = virtualSchemaTable{
 	populate: func(ctx context.Context, p *planner, _ catalog.DatabaseDescriptor, addRow func(...tree.Datum) error) error {
 		for _, vName := range varNames {
 			gen := varGen[vName]
-			value := gen.Get(&p.extendedEvalCtx)
+			value, err := gen.Get(&p.extendedEvalCtx)
+			if err != nil {
+				return err
+			}
 			if err := addRow(
 				tree.NewDString(vName),
 				tree.NewDString(value),

pkg/sql/logictest/testdata/logic_test/alter_role_set

@@ -10,15 +10,16 @@ statement ok
 ALTER ROLE test_set_role SET application_name = 'a';
 ALTER ROLE test_set_role IN DATABASE test_set_db SET application_name = 'b';
 ALTER ROLE ALL IN DATABASE test_set_db SET application_name = 'c';
-ALTER ROLE ALL SET application_name = 'd'
+ALTER ROLE ALL SET application_name = 'd';
+ALTER ROLE test_set_role SET custom_option.setting = 'e'
 
 # Verify that the defaults were stored.
 query OTT colnames
 SELECT database_id, role_name, settings FROM system.database_role_settings ORDER BY 1, 2
 ----
 database_id  role_name      settings
 0            ·              {application_name=d}
-0            test_set_role  {application_name=a}
+0            test_set_role  {application_name=a,custom_option.setting=e}
 53           ·              {application_name=c}
 53           test_set_role  {application_name=b}
 
@@ -32,7 +33,7 @@ ORDER BY 1, 2
 ----
 setdatabase  setrole    datname      rolname        setconfig
 0            0          NULL         NULL           {application_name=d}
-0            265380634  NULL         test_set_role  {application_name=a}
+0            265380634  NULL         test_set_role  {application_name=a,custom_option.setting=e}
 53           0          test_set_db  NULL           {application_name=c}
 53           265380634  test_set_db  test_set_role  {application_name=b}
 
@@ -44,7 +45,7 @@ query T
 SELECT settings FROM system.database_role_settings
 WHERE database_id = 0 AND role_name = 'test_set_role'
 ----
-{application_name=a,backslash_quote=safe_encoding}
+{application_name=a,custom_option.setting=e,backslash_quote=safe_encoding}
 
 statement ok
 ALTER ROLE test_set_role SET application_name = 'f'
@@ -54,7 +55,7 @@ query T
 SELECT settings FROM system.database_role_settings
 WHERE database_id = 0 AND role_name = 'test_set_role'
 ----
-{backslash_quote=safe_encoding,application_name=f}
+{custom_option.setting=e,backslash_quote=safe_encoding,application_name=f}
 
 statement ok
 ALTER ROLE test_set_role SET serial_normalization = 'sql_sequence';
@@ -65,7 +66,7 @@ query T
 SELECT settings FROM system.database_role_settings
 WHERE database_id = 0 AND role_name = 'test_set_role'
 ----
-{backslash_quote=safe_encoding,serial_normalization=sql_sequence}
+{custom_option.setting=e,backslash_quote=safe_encoding,serial_normalization=sql_sequence}
 
 # Resetting something that isn't there anymore is fine.
 statement ok
@@ -187,7 +188,7 @@ query OTT colnames
 SELECT database_id, role_name, settings FROM system.database_role_settings ORDER BY 1, 2
 ----
 database_id  role_name      settings
-0            test_set_role  {backslash_quote=safe_encoding,serial_normalization=sql_sequence}
+0            test_set_role  {custom_option.setting=e,backslash_quote=safe_encoding,serial_normalization=sql_sequence}
 53           ·              {application_name=c}
 53           test_set_role  {application_name=b}
 
@@ -199,7 +200,7 @@ query OTT colnames
 SELECT database_id, role_name, settings FROM system.database_role_settings ORDER BY 1, 2
 ----
 database_id  role_name      settings
-0            test_set_role  {backslash_quote=safe_encoding,serial_normalization=sql_sequence}
+0            test_set_role  {custom_option.setting=e,backslash_quote=safe_encoding,serial_normalization=sql_sequence}
 
 statement ok
 DROP ROLE test_set_role

pkg/sql/logictest/testdata/logic_test/set

@@ -414,15 +414,6 @@ SHOW idle_in_transaction_session_timeout
 statement ok
 SET idle_in_transaction_session_timeout = 0
 
-# Test that composite variable names get rejected properly, especially
-# when "tracing" is used as prefix.
-
-statement error unrecognized configuration parameter "blah.blah"
-SET blah.blah = 123
-
-statement error unrecognized configuration parameter "tracing.blah"
-SET tracing.blah = 123
-
 statement error invalid value for parameter "ssl_renegotiation_limit"
 SET ssl_renegotiation_limit = 123
 
@@ -626,3 +617,53 @@ SET LC_NUMERIC = 'en_US.UTF-8'
 
 statement error invalid value for parameter "lc_time": "en_US.UTF-8"
 SET LC_TIME = 'en_US.UTF-8'
+
+# Test custom session variables
+
+statement ok
+SET custom_option.set_SQL = 'abc';
+SELECT set_config('custom_option.set_config', 'def', false);
+RESET custom_option.use_default;
+SET tracing.custom = 'ijk'
+
+# Custom options are case insensitive.
+query T colnames
+SHOW Custom_option.set_sql
+----
+custom_option.set_sql
+abc
+
+query T
+SHOW custom_option.set_config
+----
+def
+
+query T
+SELECT current_setting('custom_option.use_default')
+----
+·
+
+statement ok
+RESET custom_option.set_config
+
+query T
+SHOW custom_option.set_config
+----
+·
+
+# Ensure it does not show up on SHOW ALL or pg_settings.
+query T
+SELECT variable FROM [SHOW ALL] WHERE variable LIKE 'custom_option.%'
+----
+
+query T
+SELECT name FROM pg_catalog.pg_settings WHERE name LIKE 'custom_option.%'
+----
+
+query T
+SHOW tracing.custom
+----
+ijk
+
+statement error unrecognized configuration parameter "custom_option.does_not_yet_exist"
+SHOW custom_option.does_not_yet_exist

pkg/sql/logictest/testdata/logic_test/set_local

@@ -508,3 +508,36 @@ query TT
 SELECT * FROM tbl
 ----
 2020-08-25 15:16:17.123456 +0000 UTC  1 day 15:16:17.123456
+
+# Verify that custom session variables are handled correctly.
+statement ok
+SET custom_option.local_setting = 'abc';
+SET custom_option.session_setting = 'abc'
+
+statement ok
+BEGIN;
+SET LOCAL custom_option.local_setting = 'def';
+SET custom_option.session_setting = 'def'
+
+query T
+SHOW custom_option.local_setting
+----
+def
+
+query T
+SHOW custom_option.session_setting
+----
+def
+
+statement ok
+COMMIT
+
+query T
+SHOW custom_option.local_setting
+----
+abc
+
+query T
+SHOW custom_option.session_setting
+----
+def

pkg/sql/opaque.go

@@ -206,6 +206,8 @@ func planOpaque(ctx context.Context, p *planner, stmt tree.Statement) (planNode,
 		return p.ShowTableStats(ctx, n)
 	case *tree.ShowTraceForSession:
 		return p.ShowTrace(ctx, n)
+	case *tree.ShowVar:
+		return p.ShowVar(ctx, n)
 	case *tree.ShowZoneConfig:
 		return p.ShowZoneConfig(ctx, n)
 	case *tree.ShowFingerprints:
@@ -293,6 +295,7 @@ func init() {
 		&tree.ShowTraceForSession{},
 		&tree.ShowZoneConfig{},
 		&tree.ShowFingerprints{},
+		&tree.ShowVar{},
 		&tree.Truncate{},
 
 		// CCL statements (without Export which has an optimizer operator).

pkg/sql/parser/sql.y

@@ -1216,6 +1216,7 @@ func (u *sqlSymUnion) setVar() *tree.SetVar {
 %type <tree.Exprs> expr_list opt_expr_list tuple1_ambiguous_values tuple1_unambiguous_values
 %type <*tree.Tuple> expr_tuple1_ambiguous expr_tuple_unambiguous
 %type <tree.NameList> attrs
+%type <[]string> session_var_parts
 %type <tree.SelectExprs> target_list
 %type <tree.UpdateExprs> set_clause_list
 %type <*tree.UpdateExpr> set_clause multiple_set_clause
@@ -4978,6 +4979,10 @@ show_session_stmt:
 
 session_var:
   IDENT
+| IDENT session_var_parts
+  {
+    $$ = $1 + "." + strings.Join($2.strs(), ".")
+  }
 // Although ALL, SESSION_USER, DATABASE, LC_COLLATE, and LC_CTYPE are
 // identifiers for the purpose of SHOW, they lex as separate token types, so
 // they need separate rules.
@@ -4994,6 +4999,16 @@ session_var:
 | TIME ZONE { $$ = "timezone" }
 | TIME error // SHOW HELP: SHOW SESSION
 
+session_var_parts:
+  '.' IDENT
+  {
+    $$.val = []string{$2}
+  }
+| session_var_parts '.' IDENT
+  {
+    $$.val = append($1.strs(), $3)
+  }
+
 // %Help: SHOW STATISTICS - display table statistics (experimental)
 // %Category: Experimental
 // %Text: SHOW STATISTICS [USING JSON] FOR TABLE <table_name>

pkg/sql/parser/testdata/set

@@ -547,3 +547,35 @@ SET LOCAL intervalstyle = 'postgres' -- normalized!
 SET LOCAL intervalstyle = ('postgres') -- fully parenthesized
 SET LOCAL intervalstyle = '_' -- literals removed
 SET LOCAL intervalstyle = 'postgres' -- identifiers removed
+
+parse
+SET a.b = 'd'
+----
+SET "a.b" = 'd' -- normalized!
+SET "a.b" = ('d') -- fully parenthesized
+SET "a.b" = '_' -- literals removed
+SET "a.b" = 'd' -- identifiers removed
+
+parse
+SET a.b.c = 'd'
+----
+SET "a.b.c" = 'd' -- normalized!
+SET "a.b.c" = ('d') -- fully parenthesized
+SET "a.b.c" = '_' -- literals removed
+SET "a.b.c" = 'd' -- identifiers removed
+
+parse
+RESET a.b.c
+----
+RESET "a.b.c" -- normalized!
+RESET "a.b.c" -- fully parenthesized
+RESET "a.b.c" -- literals removed
+RESET "a.b.c" -- identifiers removed
+
+parse
+SHOW a.b.c
+----
+SHOW "a.b.c" -- normalized!
+SHOW "a.b.c" -- fully parenthesized
+SHOW "a.b.c" -- literals removed
+SHOW "a.b.c" -- identifiers removed

pkg/sql/pg_catalog.go

@@ -2494,7 +2494,10 @@ https://www.postgresql.org/docs/9.5/catalog-pg-settings.html`,
 			if gen.Hidden {
 				continue
 			}
-			value := gen.Get(&p.extendedEvalCtx)
+			value, err := gen.Get(&p.extendedEvalCtx)
+			if err != nil {
+				return err
+			}
 			valueDatum := tree.NewDString(value)
 			var bootDatum tree.Datum = tree.DNull
 			var resetDatum tree.Datum = tree.DNull

pkg/sql/pgwire/auth.go

@@ -167,7 +167,6 @@ func (c *conn) handleAuthentication(
 			if _, ok := c.sessionArgs.SessionDefaults[keyVal[0]]; !ok {
 				c.sessionArgs.SessionDefaults[keyVal[0]] = keyVal[1]
 			}
-
 		}
 	}