> [!NOTE] > **Note:** This feature is available with the Spanner Enterprise edition and Enterprise Plus edition. For more information, see the [Spanner editions overview](https://docs.cloud.google.com/spanner/docs/editions-overview).
The page describes how Spanner Graph supports the ISO international standard query language for graph databases. Spanner Graph is based on two ISO standards: - [ISO/IEC 9075-16:2023 - Information technology --- Database languages SQL Property Graph Queries (SQL/PGQ)](https://www.iso.org/standard/79473.html), Edition 1, 2023 - [ISO/IEC 39075:2024 - Information technology --- Database languages --- GQL](https://www.iso.org/standard/76120.html), Edition 1, 2024 The following tables describe the high-level relationship between SQL/PGQ, GQL, and how Spanner Graph supports these standards. | Standard | | SQL/PGQ | GQL | Spanner Graph | |---|---|---|---|---| | Query | Graph pattern matching capabilities | Shares the core Graph Pattern Matching Language (GPML) functionalities with GQL. | Shares the core GPML functionalities with SQL/PGQ. | Both standards are supported. For more information, see Spanner Graph [GQL patterns](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns). | | Query | Other query language features (for example, `LIMIT`, `ORDER`, aggregation) | SQL-based. | Similar to SQL, but the GQL query features are linearly composable graph query statements. | Both standards are supported. For more information, see Spanner Graph [GQL query statements](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-query-statements) and [Query syntax in GoogleSQL](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/query-syntax). | | Query | Graph and table interoperability | Supported. | Not supported. | Both standards are supported. For more information, see [`GRAPH_TABLE` operator](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-sql-queries#graph_table_operator). | | Types | | Data types, functions and expressions in SQL/PGQ and GQL are similar. | Data types, functions and expressions in SQL/PGQ and GQL are similar. | Supports most data types and expressions in SQL/PGQ and GQL. For more information, see [Data types in GoogleSQL](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/data-types). | | DML | | SQL/PGQ inherits DML from SQL. | Graph-based DML is supported. | Supports SQL table-based DML. For more information, see the [GoogleSQL data manipulation language](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/dml-syntax). | | Schema | | Supports using `CREATE PROPERTY GRAPH` from tables. | Supports using `CREATE PROPERTY GRAPH` with open types and closed types. | Supports the SQL/PGQ method. For more information, see the [`CREATE PROPERTY GRAPH`](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-schema-statements#gql_create_graph) definition. | ## SQL/PGQ support > [!NOTE] > **Note:** G000 is the feature ID from the ISO SQL/PGQ standard. | Standard | SQL/PGQ feature ID | Spanner Graph | |---|---|---| | Query (Graph and table interoperability) | Feature G900: `GRAPH_TABLE` | Supported. For more information, see [`GRAPH_TABLE`](https://docs.cloud.google.com/spanner/docs/graph/queries-overview#query-graphs-and-tables-together) operator. | | Schema | Feature G924: Explicit key clause for element tables. This implies a claim of conformance to Feature G920: DDL-based SQL-property graphs. | Supported. For more information, see [`CREATE_PROPERTY_GRAPH` statement](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-schema-statements#gql_create_graph). | | Schema | Feature G925: Explicit label and properties clause for element tables. This implies a claim of conformance to Feature G920: DDL-based SQL-property graphs. | Supported. For more information, see [`CREATE_PROPERTY_GRAPH` statement](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-schema-statements#gql_create_graph). | | Query (GPML) | Feature G001: Repeatable-elements match mode. | Supported. Repeatable elements match mode is the default semantic. Explicit repeatable elements match mode clause syntax is not supported. | | Query (GPML) | Feature G008: Graph pattern `WHERE` clause. This implies a claim of conformance to Feature G000: Graph pattern. | Supported. For more information, see [Graph pattern](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#graph_pattern_definition). | | Query (GPML) | Feature G034: Path concatenation. | Supported. For more information, see see [Graph pattern](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#graph_pattern_definition). | | Query (GPML) | Feature G040: Vertex pattern. | Supported. For more information, see [Element pattern](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#element_pattern_definition). | | Query (GPML) | Feature G042: Basic full edge patterns. | Supported. For more information, see [Element pattern](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#element_pattern_definition). | | Query (GPML) | Feature G070: Label expression: label disjunction. | Supported. For more information, see [Label expression](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#label_expression_definition). | | Query (GPML) | Feature G073: Label expression: individual label name. | Supported. For more information, see [Label expression](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#label_expression_definition). | | Query (GPML) | Feature G090: Property reference. | Supported. | ## GQL support > [!NOTE] > **Note:** GG00 is the feature ID from the ISO GQL standard. | Standard | GQL feature ID | Spanner Graph | |---|---|---| | Schema | Feature GG02: Graph with a closed graph type. Conformance with at least one of GG20, GG21, GG22, or GG23: - Feature GG20: Explicit element type names. - Feature GG21: Explicit element type key label sets. - Feature GG22: Element type key label set inference. - Feature GG22: Element type key label set inference. - Feature GG23 Optional element type key label sets. | Supported. GQL support can be chosen from GG01: Graph with an open type or GG02. Spanner Graph doesn't support the exact same `CREATE_GRAPH_TYPE` statement as GQL. However, the [`CREATE_PROPERTY_GRAPH` statement](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-schema-statements#gql_create_graph) supported by Spanner Graph is closely related to GG02 (with similar support for GG20, GG21, GG22, and GG23). | | Lexical structure | "A claim of conformance to a specific version of TheUnicode® Standard and the synchronous versions of Unicode Technical Standard #10, Unicode Standard Annex #15, and Unicode Standard Annex #31. The claimed version of The Unicode® Standard shall not be less than 13.0.0." | Spanner Graph GQL shares the exact [lexical structure](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/lexical) with GoogleSQL. For reference to unicode escape values, see [Escape sequences for string and bytes literals](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/lexical#escape_sequences). | | Data types | "A claim of conformance to the set of all value types that are supported as the types of property values. At minimum, this set shall include: - The character string type specified by `STRING` or `VARCHAR`. - The boolean type specified by `BOOLEAN` or `BOOL`. - The signed regular integer type specified by `SIGNED INTEGER`, `INTEGER`, or `INT`. - The approximate numeric type specified by `FLOAT`." | Supported. For more information, see [a full list of data types](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/data-types) supported by Spanner Graph GQL. | ## Additional features The features listed in the previous sections are the minimal conformance features of the standards. Spanner Graph supports additional features in the ISO standards. To learn more, see [Spanner Graph schema overview](https://docs.cloud.google.com/spanner/docs/graph/schema-overview) and [GQL overview](https://docs.cloud.google.com/spanner/docs/reference/standard-sql/graph-intro).