Merge pull request #8391 from dolthub/taylor/info-schema

Return information_schema schema for doltgres

go/go.mod

@@ -57,7 +57,7 @@ require (
 	github.com/cespare/xxhash/v2 v2.2.0
 	github.com/creasty/defaults v1.6.0
 	github.com/dolthub/flatbuffers/v23 v23.3.3-dh.2
-	github.com/dolthub/go-mysql-server v0.18.2-0.20240923181307-5aacdb13e45a
+	github.com/dolthub/go-mysql-server v0.18.2-0.20240926171723-77ed13c03196
 	github.com/dolthub/gozstd v0.0.0-20240423170813-23a2903bca63
 	github.com/dolthub/swiss v0.1.0
 	github.com/goccy/go-json v0.10.2

go/go.sum

@@ -183,8 +183,8 @@ github.com/dolthub/fslock v0.0.3 h1:iLMpUIvJKMKm92+N1fmHVdxJP5NdyDK5bK7z7Ba2s2U=
 github.com/dolthub/fslock v0.0.3/go.mod h1:QWql+P17oAAMLnL4HGB5tiovtDuAjdDTPbuqx7bYfa0=
 github.com/dolthub/go-icu-regex v0.0.0-20240916130659-0118adc6b662 h1:aC17hZD6iwzBwwfO5M+3oBT5E5gGRiQPdn+vzpDXqIA=
 github.com/dolthub/go-icu-regex v0.0.0-20240916130659-0118adc6b662/go.mod h1:KPUcpx070QOfJK1gNe0zx4pA5sicIK1GMikIGLKC168=
-github.com/dolthub/go-mysql-server v0.18.2-0.20240923181307-5aacdb13e45a h1:rpCmZj332eiBbzsHsq3Sj5AWzl3Q7szDObwI49UqA8Y=
-github.com/dolthub/go-mysql-server v0.18.2-0.20240923181307-5aacdb13e45a/go.mod h1:lGbU2bK+QNnlETdUjOOaE+UnlEUu31VaQOFKAFGyZN4=
+github.com/dolthub/go-mysql-server v0.18.2-0.20240926171723-77ed13c03196 h1:H4bKFiOdjmhBrdjrNvYAuhfplpHM3aVFcbLXlGoD/Fc=
+github.com/dolthub/go-mysql-server v0.18.2-0.20240926171723-77ed13c03196/go.mod h1:lGbU2bK+QNnlETdUjOOaE+UnlEUu31VaQOFKAFGyZN4=
 github.com/dolthub/gozstd v0.0.0-20240423170813-23a2903bca63 h1:OAsXLAPL4du6tfbBgK0xXHZkOlos63RdKYS3Sgw/dfI=
 github.com/dolthub/gozstd v0.0.0-20240423170813-23a2903bca63/go.mod h1:lV7lUeuDhH5thVGDCKXbatwKy2KW80L4rMT46n+Y2/Q=
 github.com/dolthub/ishell v0.0.0-20240701202509-2b217167d718 h1:lT7hE5k+0nkBdj/1UOSFwjWpNxf+LCApbRHgnCA17XE=

go/libraries/doltcore/sqle/database.go

@@ -1377,6 +1377,11 @@ func (db Database) CreateSchema(ctx *sql.Context, schemaName string) error {
 
 // GetSchema implements sql.SchemaDatabase
 func (db Database) GetSchema(ctx *sql.Context, schemaName string) (sql.DatabaseSchema, bool, error) {
+	// For doltgres, the information_schema database should be a schema.
+	if schemaName == sql.InformationSchemaDatabaseName {
+		return newInformationSchemaDatabase(db.Name()), true, nil
+	}
+
 	ws, err := db.GetWorkingSet(ctx)
 	if err != nil {
 		return nil, false, err
@@ -1432,7 +1437,7 @@ func (db Database) AllSchemas(ctx *sql.Context) ([]sql.DatabaseSchema, error) {
 		return nil, err
 	}
 
-	dbSchemas := make([]sql.DatabaseSchema, len(schemas))
+	dbSchemas := make([]sql.DatabaseSchema, len(schemas)+1)
 	for i, schema := range schemas {
 		sdb := db
 		sdb.schemaName = schema.Name
@@ -1443,6 +1448,9 @@ func (db Database) AllSchemas(ctx *sql.Context) ([]sql.DatabaseSchema, error) {
 		dbSchemas[i] = handledDb
 	}
 
+	// For doltgres, the information_schema database should be a schema.
+	dbSchemas[len(schemas)] = newInformationSchemaDatabase(db.Name())
+
 	return dbSchemas, nil
 }
 

go/libraries/doltcore/sqle/index/dolt_index.go

@@ -75,6 +75,11 @@ type CommitIndex struct {
 	*doltIndex
 }
 
+// CanSupportOrderBy implements the interface sql.Index.
+func (p *CommitIndex) CanSupportOrderBy(_ sql.Expression) bool {
+	return false
+}
+
 func (p *CommitIndex) CanSupport(ranges ...sql.Range) bool {
 	var selects []string
 	for _, r := range ranges {
@@ -612,6 +617,11 @@ func (di *doltIndex) CanSupport(...sql.Range) bool {
 	return true
 }
 
+// CanSupportOrderBy implements the interface sql.Index.
+func (di *doltIndex) CanSupportOrderBy(_ sql.Expression) bool {
+	return false
+}
+
 // ColumnExpressionTypes implements the interface sql.Index.
 func (di *doltIndex) ColumnExpressionTypes() []sql.ColumnExpressionType {
 	cets := make([]sql.ColumnExpressionType, len(di.columns))

go/libraries/doltcore/sqle/information_schema_database_schema.go

@@ -0,0 +1,71 @@
+// Copyright 2019-2020 Dolthub, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package sqle
+
+import (
+	"strings"
+
+	"github.com/dolthub/go-mysql-server/sql"
+	"github.com/dolthub/go-mysql-server/sql/information_schema"
+)
+
+// informationSchemaDatabaseSchema is a DatabaseSchema implementation that provides access to the INFORMATION_SCHEMA tables. This is relevant only for Doltgres.
+type informationSchemaDatabaseSchema struct {
+	name       string
+	schemaName string
+	tables     map[string]sql.Table
+}
+
+var _ sql.DatabaseSchema = (*informationSchemaDatabaseSchema)(nil)
+
+// newInformationSchemaDatabase creates a new INFORMATION_SCHEMA DatabaseSchema for doltgres databases.
+func newInformationSchemaDatabase(dbName string) sql.DatabaseSchema {
+	isDb := &informationSchemaDatabaseSchema{
+		name:       dbName,
+		schemaName: sql.InformationSchemaDatabaseName,
+		tables:     information_schema.GetInformationSchemaTables(),
+	}
+
+	isDb.tables[information_schema.StatisticsTableName] = information_schema.NewDefaultStats()
+
+	return isDb
+}
+
+// Name implements the sql.DatabaseSchema interface.
+func (db *informationSchemaDatabaseSchema) Name() string { return db.name }
+
+// SchemaName implements the sql.DatabaseSchema interface.
+func (db *informationSchemaDatabaseSchema) SchemaName() string { return db.schemaName }
+
+// GetTableInsensitive implements the sql.DatabaseSchema interface.
+func (db *informationSchemaDatabaseSchema) GetTableInsensitive(ctx *sql.Context, tblName string) (sql.Table, bool, error) {
+	// The columns table has dynamic information that can't be cached across queries
+	if strings.ToLower(tblName) == information_schema.ColumnsTableName {
+		return information_schema.NewColumnsTable(), true, nil
+	}
+
+	tbl, ok := sql.GetTableInsensitive(tblName, db.tables)
+	return tbl, ok, nil
+}
+
+// GetTableNames implements the sql.DatabaseSchema interface.
+func (db *informationSchemaDatabaseSchema) GetTableNames(ctx *sql.Context) ([]string, error) {
+	tblNames := make([]string, 0, len(db.tables))
+	for k := range db.tables {
+		tblNames = append(tblNames, k)
+	}
+
+	return tblNames, nil
+}