thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-27 18:12:02 +00:00
Code Issues Packages Projects Releases Wiki Activity
3afc688751
ClickHouse/docs/en/sql-reference/ansi.md
DanRoscigno b50fa8b5a9 replace symlinks
2022-08-28 17:34:50 -04:00

191 lines
58 KiB
Markdown
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
slug: /en/sql-reference/ansi
sidebar_position: 40
sidebar_label: ANSI Compatibility
title: "ANSI SQL Compatibility of ClickHouse SQL Dialect"
---
:::note
This article relies on Table 38, “Feature taxonomy and definition for mandatory features”, Annex F of [ISO/IEC CD 9075-2:2011](https://www.iso.org/obp/ui/#iso:std:iso-iec:9075:-2:ed-4:v1:en:sec:8).
:::
## Differences in Behaviour
The following table lists cases when query feature works in ClickHouse, but behaves not as specified in ANSI SQL.
| Feature ID | Feature Name | Difference |
|------------|-----------------------------|-----------------------------------------------------------------------------------------------------------|
| E011 | Numeric data types | Numeric literal with period is interpreted as approximate (`Float64`) instead of exact (`Decimal`) |
| E051-05 | Select items can be renamed | Item renames have a wider visibility scope than just the SELECT result |
| E141-01 | NOT NULL constraints | `NOT NULL` is implied for table columns by default |
| E011-04 | Arithmetic operators | ClickHouse overflows instead of checked arithmetic and changes the result data type based on custom rules |
## Feature Status
| Feature ID | Feature Name | Status | Comment |
|------------|--------------------------------------------------------------------------------------------------------------------------|----------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| **E011** | **Numeric data types** | <span class="text-warning">Partial</span> | |
| E011-01 | INTEGER and SMALLINT data types | <span class="text-success">Yes</span> | |
| E011-02 | REAL, DOUBLE PRECISION and FLOAT data types data types | <span class="text-success">Yes</span> | |
| E011-03 | DECIMAL and NUMERIC data types | <span class="text-success">Yes</span> | |
| E011-04 | Arithmetic operators | <span class="text-success">Yes</span> | |
| E011-05 | Numeric comparison | <span class="text-success">Yes</span> | |
| E011-06 | Implicit casting among the numeric data types | <span class="text-danger">No</span> | ANSI SQL allows arbitrary implicit cast between numeric types, while ClickHouse relies on functions having multiple overloads instead of implicit cast |
| **E021** | **Character string types** | <span class="text-warning">Partial</span> | |
| E021-01 | CHARACTER data type | <span class="text-success">Yes</span> | |
| E021-02 | CHARACTER VARYING data type | <span class="text-success">Yes</span> | |
| E021-03 | Character literals | <span class="text-success">Yes</span> | |
| E021-04 | CHARACTER_LENGTH function | <span class="text-warning">Partial</span> | No `USING` clause |
| E021-05 | OCTET_LENGTH function | <span class="text-danger">No</span> | `LENGTH` behaves similarly |
| E021-06 | SUBSTRING | <span class="text-warning">Partial</span> | No support for `SIMILAR` and `ESCAPE` clauses, no `SUBSTRING_REGEX` variant |
| E021-07 | Character concatenation | <span class="text-warning">Partial</span> | No `COLLATE` clause |
| E021-08 | UPPER and LOWER functions | <span class="text-success">Yes</span> | |
| E021-09 | TRIM function | <span class="text-success">Yes</span> | |
| E021-10 | Implicit casting among the fixed-length and variable-length character string types | <span class="text-warning">Partial</span> | ANSI SQL allows arbitrary implicit cast between string types, while ClickHouse relies on functions having multiple overloads instead of implicit cast |
| E021-11 | POSITION function | <span class="text-warning">Partial</span> | No support for `IN` and `USING` clauses, no `POSITION_REGEX` variant |
| E021-12 | Character comparison | <span class="text-success">Yes</span> | |
| **E031** | **Identifiers** | <span class="text-warning">Partial</span>| |
| E031-01 | Delimited identifiers | <span class="text-warning">Partial</span> | Unicode literal support is limited |
| E031-02 | Lower case identifiers | <span class="text-success">Yes</span> | |
| E031-03 | Trailing underscore | <span class="text-success">Yes</span> | |
| **E051** | **Basic query specification** | <span class="text-warning">Partial</span>| |
| E051-01 | SELECT DISTINCT | <span class="text-success">Yes</span> | |
| E051-02 | GROUP BY clause | <span class="text-success">Yes</span> | |
| E051-04 | GROUP BY can contain columns not in `<select list>` | <span class="text-success">Yes</span> | |
| E051-05 | Select items can be renamed | <span class="text-success">Yes</span> | |
| E051-06 | HAVING clause | <span class="text-success">Yes</span> | |
| E051-07 | Qualified \* in select list | <span class="text-success">Yes</span> | |
| E051-08 | Correlation name in the FROM clause | <span class="text-success">Yes</span> | |
| E051-09 | Rename columns in the FROM clause | <span class="text-danger">No</span> | |
| **E061** | **Basic predicates and search conditions** | <span class="text-warning">Partial</span> | |
| E061-01 | Comparison predicate | <span class="text-success">Yes</span> | |
| E061-02 | BETWEEN predicate | <span class="text-warning">Partial</span> | No `SYMMETRIC` and `ASYMMETRIC` clause |
| E061-03 | IN predicate with list of values | <span class="text-success">Yes</span> | |
| E061-04 | LIKE predicate | <span class="text-success">Yes</span> | |
| E061-05 | LIKE predicate: ESCAPE clause | <span class="text-danger">No</span> | |
| E061-06 | NULL predicate | <span class="text-success">Yes</span> | |
| E061-07 | Quantified comparison predicate | <span class="text-danger">No</span> | |
| E061-08 | EXISTS predicate | <span class="text-danger">No</span> | |
| E061-09 | Subqueries in comparison predicate | <span class="text-success">Yes</span> | |
| E061-11 | Subqueries in IN predicate | <span class="text-success">Yes</span> | |
| E061-12 | Subqueries in quantified comparison predicate | <span class="text-danger">No</span> | |
| E061-13 | Correlated subqueries | <span class="text-danger">No</span> | |
| E061-14 | Search condition | <span class="text-success">Yes</span> | |
| **E071** | **Basic query expressions** | <span class="text-warning">Partial</span> | |
| E071-01 | UNION DISTINCT table operator | <span class="text-success">Yes</span> | |
| E071-02 | UNION ALL table operator | <span class="text-success">Yes</span> | |
| E071-03 | EXCEPT DISTINCT table operator | <span class="text-danger">No</span> | |
| E071-05 | Columns combined via table operators need not have exactly the same data type | <span class="text-success">Yes</span> | |
| E071-06 | Table operators in subqueries | <span class="text-success">Yes</span> | |
| **E081** | **Basic privileges** | <span class="text-success">Yes</span> |
| E081-01 | SELECT privilege at the table level | <span class="text-success">Yes</span> |
| E081-02 | DELETE privilege | |
| E081-03 | INSERT privilege at the table level | <span class="text-success">Yes</span> |
| E081-04 | UPDATE privilege at the table level | <span class="text-success">Yes</span> |
| E081-05 | UPDATE privilege at the column level | |
| E081-06 | REFERENCES privilege at the table level | | |
| E081-07 | REFERENCES privilege at the column level | | |
| E081-08 | WITH GRANT OPTION | <span class="text-success">Yes</span> | |
| E081-09 | USAGE privilege | | |
| E081-10 | EXECUTE privilege | | |
| **E091** | **Set functions** |<span class="text-success">Yes</span> |
| E091-01 | AVG | <span class="text-success">Yes</span> | |
| E091-02 | COUNT | <span class="text-success">Yes</span> | |
| E091-03 | MAX | <span class="text-success">Yes</span> | |
| E091-04 | MIN | <span class="text-success">Yes</span> | |
| E091-05 | SUM | <span class="text-success">Yes</span> | |
| E091-06 | ALL quantifier | <span class="text-success">Yes</span> | |
| E091-07 | DISTINCT quantifier | <span class="text-success">Yes</span> | Not all aggregate functions supported |
| **E101** | **Basic data manipulation** | <span class="text-warning">Partial</span> | |
| E101-01 | INSERT statement | <span class="text-success">Yes</span> | Note: primary key in ClickHouse does not imply the `UNIQUE` constraint |
| E101-03 | Searched UPDATE statement | <span class="text-warning">Partial</span> | There’s an `ALTER UPDATE` statement for batch data modification |
| E101-04 | Searched DELETE statement | <span class="text-warning">Partial</span> | There’s an `ALTER DELETE` statement for batch data removal |
| **E111** | **Single row SELECT statement** | <span class="text-danger">No</span> | |
| **E121** | **Basic cursor support** | <span class="text-danger">No</span> | |
| E121-01 | DECLARE CURSOR | <span class="text-danger">No</span> | |
| E121-02 | ORDER BY columns need not be in select list | <span class="text-success">Yes</span> | |
| E121-03 | Value expressions in ORDER BY clause | <span class="text-success">Yes</span> | |
| E121-04 | OPEN statement | <span class="text-danger">No</span> | |
| E121-06 | Positioned UPDATE statement | <span class="text-danger">No</span> | |
| E121-07 | Positioned DELETE statement | <span class="text-danger">No</span> | |
| E121-08 | CLOSE statement | <span class="text-danger">No</span> | |
| E121-10 | FETCH statement: implicit NEXT | <span class="text-danger">No</span> | |
| E121-17 | WITH HOLD cursors | <span class="text-danger">No</span> | |
| **E131** | **Null value support (nulls in lieu of values)** | <span class="text-success">Yes</span> | Some restrictions apply |
| **E141** | **Basic integrity constraints** | <span class="text-warning">Partial</span> | |
| E141-01 | NOT NULL constraints | <span class="text-success">Yes</span> | Note: `NOT NULL` is implied for table columns by default |
| E141-02 | UNIQUE constraint of NOT NULL columns | <span class="text-danger">No</span> | |
| E141-03 | PRIMARY KEY constraints | <span class="text-warning">Partial</span> | |
| E141-04 | Basic FOREIGN KEY constraint with the NO ACTION default for both referential delete action and referential update action | <span class="text-danger">No</span> | |
| E141-06 | CHECK constraint | <span class="text-success">Yes</span> | |
| E141-07 | Column defaults | <span class="text-success">Yes</span> | |
| E141-08 | NOT NULL inferred on PRIMARY KEY | <span class="text-success">Yes</span> | |
| E141-10 | Names in a foreign key can be specified in any order | <span class="text-danger">No</span> | |
| **E151** | **Transaction support** | <span class="text-danger">No</span> | |
| E151-01 | COMMIT statement | <span class="text-danger">No</span> | |
| E151-02 | ROLLBACK statement | <span class="text-danger">No</span> | |
| **E152** | **Basic SET TRANSACTION statement** | <span class="text-danger">No</span> | |
| E152-01 | SET TRANSACTION statement: ISOLATION LEVEL SERIALIZABLE clause | <span class="text-danger">No</span> | |
| E152-02 | SET TRANSACTION statement: READ ONLY and READ WRITE clauses | <span class="text-danger">No</span> | |
| **E153** | **Updatable queries with subqueries** | <span class="text-success">Yes</span> | |
| **E161** | **SQL comments using leading double minus** | <span class="text-success">Yes</span> | |
| **E171** | **SQLSTATE support** | <span class="text-danger">No</span> | |
| **E182** | **Host language binding** | <span class="text-danger">No</span> | |
| **F031** | **Basic schema manipulation** | <span class="text-warning">Partial</span>| |
| F031-01 | CREATE TABLE statement to create persistent base tables | <span class="text-warning">Partial</span> | No `SYSTEM VERSIONING`, `ON COMMIT`, `GLOBAL`, `LOCAL`, `PRESERVE`, `DELETE`, `REF IS`, `WITH OPTIONS`, `UNDER`, `LIKE`, `PERIOD FOR` clauses and no support for user resolved data types |
| F031-02 | CREATE VIEW statement | <span class="text-warning">Partial</span> | No `RECURSIVE`, `CHECK`, `UNDER`, `WITH OPTIONS` clauses and no support for user resolved data types |
| F031-03 | GRANT statement | <span class="text-success">Yes</span> | |
| F031-04 | ALTER TABLE statement: ADD COLUMN clause | <span class="text-success">Yes</span> | No support for `GENERATED` clause and system time period |
| F031-13 | DROP TABLE statement: RESTRICT clause | <span class="text-danger">No</span> | |
| F031-16 | DROP VIEW statement: RESTRICT clause | <span class="text-danger">No</span> | |
| F031-19 | REVOKE statement: RESTRICT clause | <span class="text-danger">No</span> | |
| **F041** | **Basic joined table** | <span class="text-warning">Partial</span> | |
| F041-01 | Inner join (but not necessarily the INNER keyword) | <span class="text-success">Yes</span> | |
| F041-02 | INNER keyword | <span class="text-success">Yes</span> | |
| F041-03 | LEFT OUTER JOIN | <span class="text-success">Yes</span> | |
| F041-04 | RIGHT OUTER JOIN | <span class="text-success">Yes</span> | |
| F041-05 | Outer joins can be nested | <span class="text-success">Yes</span> | |
| F041-07 | The inner table in a left or right outer join can also be used in an inner join | <span class="text-success">Yes</span> | |
| F041-08 | All comparison operators are supported (rather than just =) | <span class="text-danger">No</span> | |
| **F051** | **Basic date and time** | <span class="text-warning">Partial</span> | |
| F051-01 | DATE data type (including support of DATE literal) | <span class="text-success">Yes</span> | |
| F051-02 | TIME data type (including support of TIME literal) with fractional seconds precision of at least 0 | <span class="text-danger">No</span> | |
| F051-03 | TIMESTAMP data type (including support of TIMESTAMP literal) with fractional seconds precision of at least 0 and 6 | <span class="text-success">Yes</span> | |
| F051-04 | Comparison predicate on DATE, TIME, and TIMESTAMP data types | <span class="text-success">Yes</span> | |
| F051-05 | Explicit CAST between datetime types and character string types | <span class="text-success">Yes</span> | |
| F051-06 | CURRENT_DATE | <span class="text-danger">No</span> | `today()` is similar |
| F051-07 | LOCALTIME | <span class="text-danger">No</span> | `now()` is similar |
| F051-08 | LOCALTIMESTAMP | <span class="text-danger">No</span> | |
| **F081** | **UNION and EXCEPT in views** | <span class="text-warning">Partial</span> | |
| **F131** | **Grouped operations** | <span class="text-warning">Partial</span> | |
| F131-01 | WHERE, GROUP BY, and HAVING clauses supported in queries with grouped views | <span class="text-success">Yes</span> | |
| F131-02 | Multiple tables supported in queries with grouped views | <span class="text-success">Yes</span> | |
| F131-03 | Set functions supported in queries with grouped views | <span class="text-success">Yes</span> | |
| F131-04 | Subqueries with GROUP BY and HAVING clauses and grouped views | <span class="text-success">Yes</span> | |
| F131-05 | Single row SELECT with GROUP BY and HAVING clauses and grouped views | <span class="text-danger">No</span> | |
| **F181** | **Multiple module support** | <span class="text-danger">No</span> | |
| **F201** | **CAST function** | <span class="text-success">Yes</span> | |
| **F221** | **Explicit defaults** | <span class="text-danger">No</span> | |
| **F261** | **CASE expression** | <span class="text-success">Yes</span> | |
| F261-01 | Simple CASE | <span class="text-success">Yes</span> | |
| F261-02 | Searched CASE | <span class="text-success">Yes</span> | |
| F261-03 | NULLIF | <span class="text-success">Yes</span> | |
| F261-04 | COALESCE | <span class="text-success">Yes</span> | |
| **F311** | **Schema definition statement** | <span class="text-warning">Partial</span> | |
| F311-01 | CREATE SCHEMA | <span class="text-warning">Partial</span> | See CREATE DATABASE |
| F311-02 | CREATE TABLE for persistent base tables | <span class="text-success">Yes</span> | |
| F311-03 | CREATE VIEW | <span class="text-success">Yes</span> | |
| F311-04 | CREATE VIEW: WITH CHECK OPTION | <span class="text-danger">No</span> | |
| F311-05 | GRANT statement | <span class="text-success">Yes</span> | |
| **F471** | **Scalar subquery values** | <span class="text-success">Yes</span> | |
| **F481** | **Expanded NULL predicate** | <span class="text-success">Yes</span> | |
| **F812** | **Basic flagging** | <span class="text-danger">No</span> | |
| **S011** | **Distinct data types** | | |
| **T321** | **Basic SQL-invoked routines** | <span class="text-danger">No</span> | |
| T321-01 | User-defined functions with no overloading | <span class="text-danger">No</span> | |
| T321-02 | User-defined stored procedures with no overloading | <span class="text-danger">No</span> | |
| T321-03 | Function invocation | <span class="text-danger">No</span> | |
| T321-04 | CALL statement | <span class="text-danger">No</span> | |
| T321-05 | RETURN statement | <span class="text-danger">No</span> | |
| **T631** | **IN predicate with one list element** | <span class="text-success">Yes</span> | |
Reference in New Issue View Git Blame Copy Permalink