[Feature] Add StarRocks Driver Support

cli/cmd/runtime/start.go

@@ -50,6 +50,7 @@ import (
 	_ "github.com/rilldata/rill/runtime/drivers/slack"
 	_ "github.com/rilldata/rill/runtime/drivers/snowflake"
 	_ "github.com/rilldata/rill/runtime/drivers/sqlite"
+	_ "github.com/rilldata/rill/runtime/drivers/starrocks"
 	_ "github.com/rilldata/rill/runtime/reconcilers"
 	_ "github.com/rilldata/rill/runtime/resolvers"
 )

docs/docs/build/connectors/olap/starrocks.md

@@ -0,0 +1,118 @@
+---
+title: StarRocks
+description: Power Rill dashboards using StarRocks
+sidebar_label: StarRocks
+sidebar_position: 5
+---
+
+[StarRocks](https://www.starrocks.io/) is an open-source, high-performance analytical database designed for real-time, multi-dimensional analytics on large-scale data. It supports both primary key and aggregate data models, making it suitable for a variety of analytical workloads including real-time dashboards, ad-hoc queries, and complex analytical tasks.
+
+Rill supports connecting to an existing StarRocks cluster via a "live connector" and using it as an OLAP engine built against [external tables](/build/connectors/olap#external-olap-tables) to power Rill dashboards.
+
+:::
+
+## Connect to StarRocks
+
+When using StarRocks for local development, you can connect via connection parameters or by using the DSN.
+
+After selecting "Add Data", select StarRocks and fill in your connection parameters. This will automatically create the `starrocks.yaml` file in your `connectors` directory and populate the `.env` file with `connector.starrocks.password`.
+
+### Connection Parameters
+
+```yaml
+type: connector
+driver: starrocks
+
+host: <HOSTNAME>
+port: 9030
+username: <USERNAME>
+password: "{{ .env.connector.starrocks.password }}"
+catalog: default_catalog
+database: <DATABASE>
+ssl: false
+```
+
+### Connection String (DSN)
+
+Rill can also connect to StarRocks using a DSN connection string. StarRocks uses MySQL protocol, so the connection string follows the MySQL DSN format:
+
+```yaml
+type: connector
+driver: starrocks
+
+dsn: "{{ .env.connector.starrocks.dsn }}"
+```
+
+The DSN format is:
+```
+starrocks://user:password@host:port/database
+```
+
+Or using MySQL-style format:
+```
+user:password@tcp(host:port)/database?parseTime=true
+```
+
+## Configuration Properties
+
+| Property | Description | Default |
+|----------|-------------|---------|
+| `host` | StarRocks FE (Frontend) server hostname | Required |
+| `port` | MySQL protocol port of StarRocks FE | `9030` |
+| `username` | Username for authentication | Required |
+| `password` | Password for authentication | - |
+| `catalog` | StarRocks catalog name (for external catalogs like Iceberg, Hive) | `default_catalog` |
+| `database` | StarRocks database name | - |
+| `ssl` | Enable SSL/TLS encryption | `false` |
+| `dsn` | Full connection string (alternative to individual parameters) | - |
+
+## External Catalogs
+
+StarRocks supports external catalogs for querying data in Hive, Iceberg, Delta Lake, and other external data sources. To use an external catalog:
+
+1. Set the `catalog` property to your external catalog name (e.g., `iceberg_catalog`)
+2. Set the `database` property to the database within that catalog
+
+```yaml
+type: connector
+driver: starrocks
+
+host: starrocks-fe.example.com
+port: 9030
+username: analyst
+password: "{{ .env.connector.starrocks.password }}"
+catalog: iceberg_catalog
+database: my_database
+```
+
+## Naming Mapping
+
+StarRocks uses a three-level hierarchy: Catalog > Database > Table. In Rill's API:
+
+| Rill Parameter | StarRocks Concept | Example |
+|----------------|-------------------|---------|
+| `database` | Catalog | `default_catalog`, `iceberg_catalog` |
+| `databaseSchema` | Database | `my_database` |
+| `table` | Table | `my_table` |
+
+## Troubleshooting
+
+### Connection Issues
+
+If you encounter connection issues:
+
+1. Verify the FE node hostname and port (default: 9030)
+2. Check that your user has appropriate permissions
+3. Ensure network connectivity to the StarRocks FE node
+4. For SSL connections, verify SSL is enabled on the StarRocks server
+
+
+## Known Limitations
+
+- **Model execution**: Model creation and execution is not yet supported. This feature is under development.
+
+:::info Need help connecting to StarRocks?
+
+If you would like to connect Rill to an existing StarRocks instance, please don't hesitate to [contact us](/contact). We'd love to help!
+
+:::

runtime/drivers/olap.go

@@ -198,6 +198,7 @@ const (
 	DialectDruid
 	DialectClickHouse
 	DialectPinot
+	DialectStarRocks
 
 	// Below dialects are not fully supported dialects.
 	DialectBigQuery
@@ -220,6 +221,8 @@ func (d Dialect) String() string {
 		return "clickhouse"
 	case DialectPinot:
 		return "pinot"
+	case DialectStarRocks:
+		return "starrocks"
 	case DialectBigQuery:
 		return "bigquery"
 	case DialectSnowflake:
@@ -248,8 +251,8 @@ func (d Dialect) EscapeIdentifier(ident string) string {
 	}
 
 	switch d {
-	case DialectMySQL, DialectBigQuery:
-		// MySQL uses backticks for quoting identifiers
+	case DialectMySQL, DialectBigQuery, DialectStarRocks:
+		// MySQL and StarRocks use backticks for quoting identifiers
 		// Replace any backticks inside the identifier with double backticks.
 		return fmt.Sprintf("`%s`", strings.ReplaceAll(ident, "`", "``"))
 
@@ -294,7 +297,8 @@ func (d Dialect) ConvertToDateTruncSpecifier(grain runtimev1.TimeGrain) string {
 }
 
 func (d Dialect) SupportsILike() bool {
-	return d != DialectDruid && d != DialectPinot
+	// StarRocks uses MySQL syntax which doesn't support ILIKE
+	return d != DialectDruid && d != DialectPinot && d != DialectStarRocks
 }
 
 // RequiresCastForLike returns true if the dialect requires an expression used in a LIKE or ILIKE condition to explicitly be cast to type TEXT.
@@ -470,6 +474,10 @@ func (d Dialect) JoinOnExpression(lhs, rhs string) string {
 	if d == DialectClickHouse {
 		return fmt.Sprintf("isNotDistinctFrom(%s, %s)", lhs, rhs)
 	}
+	// StarRocks uses MySQL's NULL-safe equal operator
+	if d == DialectStarRocks {
+		return fmt.Sprintf("%s <=> %s", lhs, rhs)
+	}
 	return fmt.Sprintf("%s IS NOT DISTINCT FROM %s", lhs, rhs)
 }
 
@@ -581,6 +589,10 @@ func (d Dialect) DateTruncExpr(dim *runtimev1.MetricsViewSpec_Dimension, grain r
 			return fmt.Sprintf("CAST(date_trunc('%s', %s, 'MILLISECONDS') AS TIMESTAMP)", specifier, expr), nil
 		}
 		return fmt.Sprintf("CAST(date_trunc('%s', %s, 'MILLISECONDS', '%s') AS TIMESTAMP)", specifier, expr, tz), nil
+	case DialectStarRocks:
+		// StarRocks supports date_trunc similar to DuckDB but does not support timezone parameter
+		// NOTE: Timezone and time shift parameters are validated in runtime/metricsview/executor/executor_validate.go
+		return fmt.Sprintf("date_trunc('%s', %s)", specifier, expr), nil
 	default:
 		return "", fmt.Errorf("unsupported dialect %q", d)
 	}
@@ -593,7 +605,7 @@ func (d Dialect) DateDiff(grain runtimev1.TimeGrain, t1, t2 time.Time) (string,
 		return fmt.Sprintf("DATEDIFF('%s', parseDateTimeBestEffort('%s'), parseDateTimeBestEffort('%s'))", unit, t1.Format(time.RFC3339), t2.Format(time.RFC3339)), nil
 	case DialectDruid:
 		return fmt.Sprintf("TIMESTAMPDIFF(%q, TIME_PARSE('%s'), TIME_PARSE('%s'))", unit, t1.Format(time.RFC3339), t2.Format(time.RFC3339)), nil
-	case DialectDuckDB:
+	case DialectDuckDB, DialectStarRocks:
 		return fmt.Sprintf("DATEDIFF('%s', TIMESTAMP '%s', TIMESTAMP '%s')", unit, t1.Format(time.RFC3339), t2.Format(time.RFC3339)), nil
 	case DialectPinot:
 		return fmt.Sprintf("DATEDIFF('%s', %d, %d)", unit, t1.UnixMilli(), t2.UnixMilli()), nil
@@ -604,7 +616,7 @@ func (d Dialect) DateDiff(grain runtimev1.TimeGrain, t1, t2 time.Time) (string,
 
 func (d Dialect) IntervalSubtract(tsExpr, unitExpr string, grain runtimev1.TimeGrain) (string, error) {
 	switch d {
-	case DialectClickHouse, DialectDruid, DialectDuckDB:
+	case DialectClickHouse, DialectDruid, DialectDuckDB, DialectStarRocks:
 		return fmt.Sprintf("(%s - INTERVAL (%s) %s)", tsExpr, unitExpr, d.ConvertToDateTruncSpecifier(grain)), nil
 	case DialectPinot:
 		return fmt.Sprintf("CAST((dateAdd('%s', -1 * %s, %s)) AS TIMESTAMP)", d.ConvertToDateTruncSpecifier(grain), unitExpr, tsExpr), nil
@@ -650,6 +662,18 @@ func (d Dialect) SelectTimeRangeBins(start, end time.Time, grain runtimev1.TimeG
 		}
 		sb.WriteString(fmt.Sprintf(") t (%s)", d.EscapeIdentifier(alias)))
 		return sb.String(), args, nil
+	case DialectStarRocks:
+		// StarRocks uses UNION ALL for generating time series
+		var sb strings.Builder
+		first := true
+		for t := start; t != end; t = timeutil.OffsetTime(t, g, 1, tz) {
+			if !first {
+				sb.WriteString(" UNION ALL ")
+			}
+			sb.WriteString(fmt.Sprintf("SELECT CAST('%s' AS DATETIME) AS %s", t.Format(time.DateTime), d.EscapeIdentifier(alias)))
+			first = false
+		}
+		return sb.String(), nil, nil
 	default:
 		return "", nil, fmt.Errorf("unsupported dialect %q", d)
 	}
@@ -847,6 +871,8 @@ func (d Dialect) GetTimeExpr(t time.Time) (bool, string) {
 		return true, fmt.Sprintf("CAST('%s' AS TIMESTAMP)", t.Format(time.RFC3339Nano))
 	case DialectPinot:
 		return true, fmt.Sprintf("CAST(%d AS TIMESTAMP)", t.UnixMilli())
+	case DialectStarRocks:
+		return true, fmt.Sprintf("CAST('%s' AS DATETIME)", t.Format(time.DateTime))
 	default:
 		return false, ""
 	}