Support ON and use default database for SHOW commands

Normalize all of the SHOW commands so they allow both using ON to
specify the database and using the default database. Some commands would
require one and some would require the other and it was confusing when
using the query language.

Affected commands:

* SHOW RETENTION POLICIES
* SHOW MEASUREMENTS
* SHOW SERIES
* SHOW TAG KEYS
* SHOW TAG VALUES
* SHOW FIELD KEYS

CHANGELOG.md

@@ -10,6 +10,7 @@
 - [#7099](https://github.com/influxdata/influxdb/pull/7099): Implement text/csv content encoding for the response writer.
 - [#6992](https://github.com/influxdata/influxdb/issues/6992): Support tools for running async queries.
 - [#7136](https://github.com/influxdata/influxdb/pull/7136): Update jwt-go dependency to version 3.
+- [#6962](https://github.com/influxdata/influxdb/issues/6962): Support ON and use default database for SHOW commands.
 
 ### Bugfixes
 

coordinator/statement_executor.go

@@ -672,11 +672,11 @@ func (e *StatementExecutor) executeShowGrantsForUserStatement(q *influxql.ShowGr
 }
 
 func (e *StatementExecutor) executeShowMeasurementsStatement(q *influxql.ShowMeasurementsStatement, ctx *influxql.ExecutionContext) error {
-	if ctx.Database == "" {
+	if q.Database == "" {
 		return ErrDatabaseNameRequired
 	}
 
-	measurements, err := e.TSDBStore.Measurements(ctx.Database, q.Condition)
+	measurements, err := e.TSDBStore.Measurements(q.Database, q.Condition)
 	if err != nil || len(measurements) == 0 {
 		ctx.Results <- &influxql.Result{
 			StatementID: ctx.StatementID,
@@ -723,6 +723,10 @@ func (e *StatementExecutor) executeShowMeasurementsStatement(q *influxql.ShowMea
 }
 
 func (e *StatementExecutor) executeShowRetentionPoliciesStatement(q *influxql.ShowRetentionPoliciesStatement) (models.Rows, error) {
+	if q.Database == "" {
+		return nil, ErrDatabaseNameRequired
+	}
+
 	di := e.MetaClient.Database(q.Database)
 	if di == nil {
 		return nil, influxdb.ErrDatabaseNotFound(q.Database)
@@ -1068,6 +1072,14 @@ func (e *StatementExecutor) NormalizeStatement(stmt influxql.Statement, defaultD
 			return
 		}
 		switch node := node.(type) {
+		case *influxql.ShowRetentionPoliciesStatement:
+			if node.Database == "" {
+				node.Database = defaultDatabase
+			}
+		case *influxql.ShowMeasurementsStatement:
+			if node.Database == "" {
+				node.Database = defaultDatabase
+			}
 		case *influxql.Measurement:
 			err = e.normalizeMeasurement(node, defaultDatabase)
 		}

influxql/ast.go

@@ -2245,6 +2245,10 @@ func (s *DeleteStatement) RequiredPrivileges() (ExecutionPrivileges, error) {
 
 // ShowSeriesStatement represents a command for listing series in the database.
 type ShowSeriesStatement struct {
+	// Database to query. If blank, use the default database.
+	// The database can also be specified per source in the Sources.
+	Database string
+
 	// Measurement(s) the series are listed for.
 	Sources Sources
 
@@ -2267,6 +2271,10 @@ func (s *ShowSeriesStatement) String() string {
 	var buf bytes.Buffer
 	_, _ = buf.WriteString("SHOW SERIES")
 
+	if s.Database != "" {
+		_, _ = buf.WriteString(" ON ")
+		_, _ = buf.WriteString(QuoteIdent(s.Database))
+	}
 	if s.Sources != nil {
 		_, _ = buf.WriteString(" FROM ")
 		_, _ = buf.WriteString(s.Sources.String())
@@ -2518,6 +2526,9 @@ func (s *DropContinuousQueryStatement) RequiredPrivileges() (ExecutionPrivileges
 
 // ShowMeasurementsStatement represents a command for listing measurements.
 type ShowMeasurementsStatement struct {
+	// Database to query. If blank, use the default database.
+	Database string
+
 	// Measurement name or regex.
 	Source Source
 
@@ -2540,6 +2551,10 @@ func (s *ShowMeasurementsStatement) String() string {
 	var buf bytes.Buffer
 	_, _ = buf.WriteString("SHOW MEASUREMENTS")
 
+	if s.Database != "" {
+		_, _ = buf.WriteString(" ON ")
+		_, _ = buf.WriteString(s.Database)
+	}
 	if s.Source != nil {
 		_, _ = buf.WriteString(" WITH MEASUREMENT ")
 		if m, ok := s.Source.(*Measurement); ok && m.Regex != nil {
@@ -2614,8 +2629,11 @@ type ShowRetentionPoliciesStatement struct {
 // String returns a string representation of a ShowRetentionPoliciesStatement.
 func (s *ShowRetentionPoliciesStatement) String() string {
 	var buf bytes.Buffer
-	_, _ = buf.WriteString("SHOW RETENTION POLICIES ON ")
-	_, _ = buf.WriteString(QuoteIdent(s.Database))
+	_, _ = buf.WriteString("SHOW RETENTION POLICIES")
+	if s.Database != "" {
+		_, _ = buf.WriteString(" ON ")
+		_, _ = buf.WriteString(QuoteIdent(s.Database))
+	}
 	return buf.String()
 }
 
@@ -2759,6 +2777,10 @@ func (s *ShowSubscriptionsStatement) RequiredPrivileges() (ExecutionPrivileges,
 
 // ShowTagKeysStatement represents a command for listing tag keys.
 type ShowTagKeysStatement struct {
+	// Database to query. If blank, use the default database.
+	// The database can also be specified per source in the Sources.
+	Database string
+
 	// Data sources that fields are extracted from.
 	Sources Sources
 
@@ -2786,6 +2808,10 @@ func (s *ShowTagKeysStatement) String() string {
 	var buf bytes.Buffer
 	_, _ = buf.WriteString("SHOW TAG KEYS")
 
+	if s.Database != "" {
+		_, _ = buf.WriteString(" ON ")
+		_, _ = buf.WriteString(QuoteIdent(s.Database))
+	}
 	if s.Sources != nil {
 		_, _ = buf.WriteString(" FROM ")
 		_, _ = buf.WriteString(s.Sources.String())
@@ -2824,6 +2850,10 @@ func (s *ShowTagKeysStatement) RequiredPrivileges() (ExecutionPrivileges, error)
 
 // ShowTagValuesStatement represents a command for listing tag values.
 type ShowTagValuesStatement struct {
+	// Database to query. If blank, use the default database.
+	// The database can also be specified per source in the Sources.
+	Database string
+
 	// Data source that fields are extracted from.
 	Sources Sources
 
@@ -2852,6 +2882,10 @@ func (s *ShowTagValuesStatement) String() string {
 	var buf bytes.Buffer
 	_, _ = buf.WriteString("SHOW TAG VALUES")
 
+	if s.Database != "" {
+		_, _ = buf.WriteString(" ON ")
+		_, _ = buf.WriteString(QuoteIdent(s.Database))
+	}
 	if s.Sources != nil {
 		_, _ = buf.WriteString(" FROM ")
 		_, _ = buf.WriteString(s.Sources.String())
@@ -2903,6 +2937,10 @@ func (s *ShowUsersStatement) RequiredPrivileges() (ExecutionPrivileges, error) {
 
 // ShowFieldKeysStatement represents a command for listing field keys.
 type ShowFieldKeysStatement struct {
+	// Database to query. If blank, use the default database.
+	// The database can also be specified per source in the Sources.
+	Database string
+
 	// Data sources that fields are extracted from.
 	Sources Sources
 
@@ -2922,6 +2960,10 @@ func (s *ShowFieldKeysStatement) String() string {
 	var buf bytes.Buffer
 	_, _ = buf.WriteString("SHOW FIELD KEYS")
 
+	if s.Database != "" {
+		_, _ = buf.WriteString(" ON ")
+		_, _ = buf.WriteString(QuoteIdent(s.Database))
+	}
 	if s.Sources != nil {
 		_, _ = buf.WriteString(" FROM ")
 		_, _ = buf.WriteString(s.Sources.String())

influxql/parser.go

@@ -1045,6 +1045,17 @@ func (p *Parser) parseShowSeriesStatement() (*ShowSeriesStatement, error) {
 	stmt := &ShowSeriesStatement{}
 	var err error
 
+	// Parse optional ON clause.
+	if tok, _, _ := p.scanIgnoreWhitespace(); tok == ON {
+		// Parse the database.
+		stmt.Database, err = p.parseIdent()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		p.unscan()
+	}
+
 	// Parse optional FROM.
 	if tok, _, _ := p.scanIgnoreWhitespace(); tok == FROM {
 		if stmt.Sources, err = p.parseSources(); err != nil {
@@ -1083,6 +1094,17 @@ func (p *Parser) parseShowMeasurementsStatement() (*ShowMeasurementsStatement, e
 	stmt := &ShowMeasurementsStatement{}
 	var err error
 
+	// Parse optional ON clause.
+	if tok, _, _ := p.scanIgnoreWhitespace(); tok == ON {
+		// Parse the database.
+		stmt.Database, err = p.parseIdent()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		p.unscan()
+	}
+
 	// Parse optional WITH clause.
 	if tok, _, _ := p.scanIgnoreWhitespace(); tok == WITH {
 		// Parse required MEASUREMENT token.
@@ -1141,16 +1163,16 @@ func (p *Parser) parseShowRetentionPoliciesStatement() (*ShowRetentionPoliciesSt
 	stmt := &ShowRetentionPoliciesStatement{}
 
 	// Expect an "ON" keyword.
-	if tok, pos, lit := p.scanIgnoreWhitespace(); tok != ON {
-		return nil, newParseError(tokstr(tok, lit), []string{"ON"}, pos)
-	}
-
-	// Parse the database.
-	ident, err := p.parseIdent()
-	if err != nil {
-		return nil, err
+	if tok, _, _ := p.scanIgnoreWhitespace(); tok == ON {
+		// Parse the database.
+		ident, err := p.parseIdent()
+		if err != nil {
+			return nil, err
+		}
+		stmt.Database = ident
+	} else {
+		p.unscan()
 	}
-	stmt.Database = ident
 
 	return stmt, nil
 }
@@ -1161,6 +1183,17 @@ func (p *Parser) parseShowTagKeysStatement() (*ShowTagKeysStatement, error) {
 	stmt := &ShowTagKeysStatement{}
 	var err error
 
+	// Parse optional ON clause.
+	if tok, _, _ := p.scanIgnoreWhitespace(); tok == ON {
+		// Parse the database.
+		stmt.Database, err = p.parseIdent()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		p.unscan()
+	}
+
 	// Parse optional source.
 	if tok, _, _ := p.scanIgnoreWhitespace(); tok == FROM {
 		if stmt.Sources, err = p.parseSources(); err != nil {
@@ -1209,6 +1242,17 @@ func (p *Parser) parseShowTagValuesStatement() (*ShowTagValuesStatement, error)
 	stmt := &ShowTagValuesStatement{}
 	var err error
 
+	// Parse optional ON clause.
+	if tok, _, _ := p.scanIgnoreWhitespace(); tok == ON {
+		// Parse the database.
+		stmt.Database, err = p.parseIdent()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		p.unscan()
+	}
+
 	// Parse optional source.
 	if tok, _, _ := p.scanIgnoreWhitespace(); tok == FROM {
 		if stmt.Sources, err = p.parseSources(); err != nil {
@@ -1314,6 +1358,17 @@ func (p *Parser) parseShowFieldKeysStatement() (*ShowFieldKeysStatement, error)
 	stmt := &ShowFieldKeysStatement{}
 	var err error
 
+	// Parse optional ON clause.
+	if tok, _, _ := p.scanIgnoreWhitespace(); tok == ON {
+		// Parse the database.
+		stmt.Database, err = p.parseIdent()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		p.unscan()
+	}
+
 	// Parse optional source.
 	if tok, _, _ := p.scanIgnoreWhitespace(); tok == FROM {
 		if stmt.Sources, err = p.parseSources(); err != nil {

influxql/parser_test.go

@@ -1035,6 +1035,14 @@ func TestParser_ParseStatement(t *testing.T) {
 			},
 		},
 
+		// SHOW SERIES ON db0
+		{
+			s: `SHOW SERIES ON db0`,
+			stmt: &influxql.ShowSeriesStatement{
+				Database: "db0",
+			},
+		},
+
 		// SHOW SERIES FROM /<regex>/
 		{
 			s: `SHOW SERIES FROM /[cg]pu/`,
@@ -1097,6 +1105,14 @@ func TestParser_ParseStatement(t *testing.T) {
 			},
 		},
 
+		// SHOW MEASUREMENTS ON db0
+		{
+			s: `SHOW MEASUREMENTS ON db0`,
+			stmt: &influxql.ShowMeasurementsStatement{
+				Database: "db0",
+			},
+		},
+
 		// SHOW MEASUREMENTS WITH MEASUREMENT = cpu
 		{
 			s: `SHOW MEASUREMENTS WITH MEASUREMENT = cpu`,
@@ -1140,9 +1156,15 @@ func TestParser_ParseStatement(t *testing.T) {
 
 		// SHOW RETENTION POLICIES
 		{
-			s: `SHOW RETENTION POLICIES ON mydb`,
+			s:    `SHOW RETENTION POLICIES`,
+			stmt: &influxql.ShowRetentionPoliciesStatement{},
+		},
+
+		// SHOW RETENTION POLICIES ON db0
+		{
+			s: `SHOW RETENTION POLICIES ON db0`,
 			stmt: &influxql.ShowRetentionPoliciesStatement{
-				Database: "mydb",
+				Database: "db0",
 			},
 		},
 
@@ -1154,6 +1176,14 @@ func TestParser_ParseStatement(t *testing.T) {
 			},
 		},
 
+		// SHOW TAG KEYS ON db0
+		{
+			s: `SHOW TAG KEYS ON db0`,
+			stmt: &influxql.ShowTagKeysStatement{
+				Database: "db0",
+			},
+		},
+
 		// SHOW TAG KEYS with LIMIT
 		{
 			s: `SHOW TAG KEYS FROM src LIMIT 2`,
@@ -1357,6 +1387,16 @@ func TestParser_ParseStatement(t *testing.T) {
 			},
 		},
 
+		// SHOW TAG VALUES ON db0
+		{
+			s: `SHOW TAG VALUES ON db0 WITH KEY = "host"`,
+			stmt: &influxql.ShowTagValuesStatement{
+				Database:   "db0",
+				Op:         influxql.EQ,
+				TagKeyExpr: &influxql.StringLiteral{Val: "host"},
+			},
+		},
+
 		// SHOW USERS
 		{
 			s:    `SHOW USERS`,
@@ -1387,6 +1427,12 @@ func TestParser_ParseStatement(t *testing.T) {
 				},
 			},
 		},
+		{
+			s: `SHOW FIELD KEYS ON db0`,
+			stmt: &influxql.ShowFieldKeysStatement{
+				Database: "db0",
+			},
+		},
 
 		// DELETE statement
 		{
@@ -2168,8 +2214,6 @@ func TestParser_ParseStatement(t *testing.T) {
 		{s: `SHOW CONTINUOUS`, err: `found EOF, expected QUERIES at line 1, char 17`},
 		{s: `SHOW RETENTION`, err: `found EOF, expected POLICIES at line 1, char 16`},
 		{s: `SHOW RETENTION ON`, err: `found ON, expected POLICIES at line 1, char 16`},
-		{s: `SHOW RETENTION POLICIES`, err: `found EOF, expected ON at line 1, char 25`},
-		{s: `SHOW RETENTION POLICIES mydb`, err: `found mydb, expected ON at line 1, char 25`},
 		{s: `SHOW RETENTION POLICIES ON`, err: `found EOF, expected identifier at line 1, char 28`},
 		{s: `SHOW SHARD`, err: `found EOF, expected GROUPS at line 1, char 12`},
 		{s: `SHOW FOO`, err: `found FOO, expected CONTINUOUS, DATABASES, DIAGNOSTICS, FIELD, GRANTS, MEASUREMENTS, QUERIES, RETENTION, SERIES, SHARD, SHARDS, STATS, SUBSCRIPTIONS, TAG, USERS at line 1, char 6`},