SQL Conformance
Databend aims to conform to the SQL standard, with particular support for ISO/IEC 9075:2011, also known as SQL:2011. While not an exhaustive statement of conformance, Databend incorporates many features required by the SQL standard, often with slight differences in syntax or function. This page outlines the level of conformity of Databend to the SQL:2011 standard.
| Feature ID | Feature Name | Supported? | Note |
|---|---|---|---|
| E011 | Numeric data types | Yes | |
| E011-01 | INTEGER and SMALLINT data types | Yes | |
| E011-02 | REAL, DOUBLE PRECISION and FLOAT data types | Yes | |
| E011-03 | DECIMAL and NUMERIC data types | Yes | |
| E011-04 | Arithmetic operators | Yes | |
| E011-05 | Numeric comparison | Yes | |
| E011-06 | Implicit casting among the numeric data types | Yes | |
| E021 | Character string types | Partial | |
| E021-01 | CHARACTER data type | No | Fixed-length string type not supported |
| E021-02 | CHARACTER VARYING data type | Yes | |
| E021-03 | Character literals | Yes | |
| E021-04 | CHARACTER_LENGTH function | Yes | |
| E021-05 | OCTET_LENGTH function | No | |
| E021-06 | SUBSTRING | Yes | |
| E021-07 | Character concatenation | Yes | |
| E021-08 | UPPER and LOWER functions | Yes | |
| E021-09 | TRIM function | Yes | |
| E021-10 | Implicit casting among the fixed-length and variable-length character string types | No | Fixed-length string type not supported |
| E021-11 | POSITION function | Yes | |
| E021-12 | Character comparison | Yes | |
| E031 | Identifiers | Yes | |
| E031-01 | Delimited identifiers | Yes | |
| E031-02 | Lower case identifiers | Yes | |
| E031-03 | Trailing underscore | Yes | |
| E051 | Basic query specification | Partial | |
| E051-01 | SELECT DISTINCT | Yes | |
| E051-02 | GROUP BY clause | Yes | |
| E051-04 | GROUP BY can contain columns not in SELECT list | Yes | |
| E051-05 | Select items can be renamed | Yes | |
| E051-06 | HAVING clause | Yes | |
| E051-07 | Qualified * in select list | No | |
| E051-08 | Correlation name in the FROM clause | Yes | |
| E051-09 | Rename columns in the FROM clause | No | |
| E061 | Basic predicates and search conditions | Partial | |
| E061-01 | Comparison predicate | Yes | |
| E061-02 | BETWEEN predicate | Yes | |
| E061-03 | IN predicate with list of values | Yes | |
| E061-04 | LIKE predicate | Yes | |
| E061-05 | LIKE predicate: ESCAPE clause | No | |
| E061-06 | NULL predicate | Yes | |
| E061-07 | Quantified comparison predicate | Yes | |
| E061-08 | EXISTS predicate | Yes | |
| E061-09 | Subqueries in comparison predicate | Yes | |
| E061-11 | Subqueries in IN predicate | Yes | |
| E061-12 | Subqueries in quantified comparison predicate | Yes | |
| E061-13 | Correlated subqueries | Yes | |
| E061-14 | Search condition | Yes | |
| E071 | Basic query expressions | Partial | |
| E071-01 | UNION DISTINCT table operator | Yes | |
| E071-02 | UNION ALL table operator | Yes | |
| E071-03 | EXCEPT DISTINCT table operator | Yes | |
| E071-05 | Columns combined via table operators need not have exactly the same data type | Partial | Only columns with data types that can be implicitly coerced are allowed to be combined with table operators. |
| E071-06 | Table operators in subqueries | Yes | |
| E081 | Basic privileges | Partial | |
| E081-01 | SELECT privilege at the table level | Yes | |
| E081-02 | DELETE privilege | Yes | |
| E081-03 | INSERT privilege at the table level | Yes | |
| E081-04 | UPDATE privilege at the table level | Yes | |
| E081-05 | UPDATE privilege at the column level | No | |
| E081-06 | REFERENCES privilege at the table level | No | |
| E081-07 | REFERENCES privilege at the column level | No | |
| E081-08 | WITH GRANT OPTION | No | |
| E081-09 | USAGE privilege | No | |
| E081-10 | EXECUTE privilege | No | |
| E091 | Set functions | Yes | |
| E091-01 | AVG | Yes | |
| E091-02 | COUNT | Yes | |
| E091-03 | MAX | Yes | |
| E091-04 | MIN | Yes | |
| E091-05 | SUM | Yes | |
| E091-06 | ALL quantifier | Yes | |
| E091-07 | DISTINCT quantifier | Partial | Currently, Databend supports COUNT(DISTINCT ...) and SELECT DISTINCT ... queries. |
| E101 | Basic data manipulation | Partial | |
| E101-01 | INSERT statement | Yes | |
| E101-03 | Searched UPDATE statement | Yes | |
| E101-04 | Searched DELETE statement | Yes | |
| E111 | Single row SELECT statement | Yes | |
| E121 | Basic cursor support | Partial | |
| E121-01 | DECLARE CURSOR | No | |
| E121-02 | ORDER BY columns need not be in select list | Yes | |
| E121-03 | Value expressions in ORDER BY clause | Yes | |
| E121-04 | OPEN statement | No | |
| E121-06 | Positioned UPDATE statement | No | |
| E121-07 | Positioned DELETE statement | No | |
| E121-08 | CLOSE statement | No | |
| E121-10 | FETCH statement: implicit NEXT | No | |
| E121-17 | WITH HOLD cursors | No | |
| E131 | Null value support (nulls in lieu of values) | Yes | |
| E141 | Basic integrity constraints | No | |
| E141-01 | NOT NULL constraints | Yes | Default in Databend: All columns are nullable. |
| E141-02 | UNIQUE constraint of NOT NULL columns | No | |
| E141-03 | PRIMARY KEY constraints | No | |
| E141-04 | Basic FOREIGN KEY constraint with the NO ACTION default for both referential delete action and referential update action | No | |
| E141-06 | CHECK constraint | No | |
| E141-07 | Column defaults | Yes | |
| E141-08 | NOT NULL inferred on PRIMARY KEY | No | |
| E141-10 | Names in a foreign key can be specified in any order | No | |
| E151 | Transaction support | Partial | |
| E151-01 | COMMIT statement | Partial | Databend only supports implicit transactions for every individual DML statement. |
| E151-02 | ROLLBACK statement | No | |
| E152 | Basic SET TRANSACTION statement | No | |
| E152-01 | SET TRANSACTION statement: ISOLATION LEVEL SERIALIZABLE clause | No | |
| E152-02 | SET TRANSACTION statement: READ ONLY and READ WRITE clauses | No | |
| E153 | Updatable queries with subqueries | Yes | |
| E161 | SQL comments using leading double minus | Yes | |
| E171 | SQLSTATE support | No | |
| E182 | Host language binding | No | |
| F031 | Basic schema manipulation | Yes | |
| F031-01 | CREATE TABLE statement to create persistent base tables | Yes | |
| F031-02 | CREATE VIEW statement | Yes | |
| F031-03 | GRANT statement | Partial | |
| F031-04 | ALTER TABLE statement: ADD COLUMN clause | Yes | |
| F031-13 | DROP TABLE statement: RESTRICT clause | Partial | |
| F031-16 | DROP VIEW statement: RESTRICT clause | Partial | |
| F031-19 | REVOKE statement: RESTRICT clause | Partial | |
| F041 | Basic joined table | Yes | |
| F041-01 | Inner join (but not necessarily the INNER keyword) | Yes | |
| F041-02 | INNER keyword | Yes | |
| F041-03 | LEFT OUTER JOIN | Yes | |
| F041-04 | RIGHT OUTER JOIN | Yes | |
| F041-05 | Outer joins can be nested | Yes | |
| F041-07 | The inner table in a left or right outer join can also be used in an inner join | Yes | |
| F041-08 | All comparison operators are supported (rather than just =) | Yes | |
| F051 | Basic date and time | Partial | |
| F051-01 | DATE data type (including support of DATE literal) | Yes | |
| F051-02 | TIME data type (including support of TIME literal) with fractional seconds precision of at least 0 | No | |
| F051-03 | TIMESTAMP data type (including support of TIMESTAMP literal) with fractional seconds precision of at least 0 and 6 | Yes | |
| F051-04 | Comparison predicate on DATE, TIME, and TIMESTAMP data types | Yes | |
| F051-05 | Explicit CAST between datetime types and character string types | Yes | |
| F051-06 | CURRENT_DATE | Yes | |
| F051-07 | LOCALTIME | Yes | |
| F051-08 | LOCALTIMESTAMP | Yes | |
| F081 | UNION and EXCEPT in views | Yes | |
| F131 | Grouped operations | Yes | |
| F131-01 | WHERE, GROUP BY, and HAVING clauses supported in queries with grouped views | Yes | |
| F131-02 | Multiple tables supported in queries with grouped views | Yes | |
| F131-03 | Set functions supported in queries with grouped views | Yes | |
| F131-04 | Subqueries with GROUP BY and HAVING clauses and grouped views | Yes | |
| F131-05 | Single row SELECT with GROUP BY and HAVING clauses and grouped views | Yes | |
| F181 | Multiple module support | No | |
| F201 | CAST function | Yes | |
| F221 | Explicit defaults | No | |
| F261 | CASE expression | Yes | |
| F261-01 | Simple CASE | Yes | |
| F261-02 | Searched CASE | Yes | |
| F261-03 | NULLIF | Yes | |
| F261-04 | COALESCE | Yes | |
| F311 | Schema definition statement | Partial | |
| F311-01 | CREATE SCHEMA | Yes | |
| F311-02 | CREATE TABLE for persistent base tables | Yes | |
| F311-03 | CREATE VIEW | Yes | |
| F311-04 | CREATE VIEW: WITH CHECK OPTION | No | |
| F311-05 | GRANT statement | Partial | |
| F471 | Scalar subquery values | Yes | |
| F481 | Expanded NULL predicate | Yes | |
| F812 | Basic flagging | No | |
| S011 | Distinct data types | No | |
| T321 | Basic SQL-invoked routines | No | |
| T321-01 | User-defined functions with no overloading | Yes | |
| T321-02 | User-defined stored procedures with no overloading | No | |
| T321-03 | Function invocation | Yes | |
| T321-04 | CALL statement | No | |
| T321-05 | RETURN statement | No | |
| T631 | IN predicate with one list element | Yes |