typefox/langium-sql

Language server for SQL in Langium

langium-sql's Issues

Missing for MySQL use cases

• WITH clause
• BETWEEN x AND y operator
• LIKE operator
• IN operator
• IS operator
• CONCAT || operator
• several scalar functions
  • APPROX_COUNT_DISTINCT_ESTIMATE
  • unhex
  • concat
  • date
  • pow
  • date_trunc
  • last
  • u256_to_decimal
• set functions
  • sum

Function calls

Needs to be refined

• which functions are needed
• find out differences between set functions and normal functions
• find out how to define them as 'system library'
• implement actual functions one by one

Create an interpreter

Requirements:

• gets the SQL input model
• gets tables via interface
• evaluates the SQL query
• returns the result

Good for:

• value tests for ORDER BY and DISTINCT
• demo page

Add enumerations

They are currently not displayable.

Casts

A cast is called like this: CAST (value AS targetType) and convert a value into another type.

Casts are orthogonal to the type system: There are cast rules for each data type (cast is allowed/not allowed, what is the outcome).

Here is the documentation for all data types:

• Number
• Bit strings
• Binary strings
• Character strings
• Temporal values
• Booleans
• References

Split this task as desired.

Argument of type 'undefined' is not assignable to parameter of type 'never'

when i compile this project, i get error mssages as blow:

src/sql-scope-provider.ts:131:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

131                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:140:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

140                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:149:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

149                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:166:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

166                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:177:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

177                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:210:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

210                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:220:39 - error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'never'.

220                     assertUnreachable(property);
                                          ~~~~~~~~

src/sql-scope-provider.ts:231:31 - error TS2345: Argument of type 'ColumnDefinition | ExpressionQuery | NumberLiteral | StringLiteral | CatalogDefinition | ... 45 more ... | TopClause' is not assignable to parameter of type 'never'.
  Type 'ColumnDefinition' is not assignable to type 'never'.

231             assertUnreachable(container);

my environment :
node: v18.20.1
typescript: v5.4.4

What can i do to fix it ?

Function call using SelectElements for parameters

I'm not sure the SimpleSelectStatement.select and PrimaryExpression.FunctionCall rules are correct.

I'm assuming FunctionCall is intended to parse system function calls (E.g. ABS() or DATEADD(), etc)

Problems:

1. It currently uses the SelectElements rule for its params property;

{infer FunctionCall} function=GlobalReference '(' params=SelectElements? ')' 
      overClause=OverClause?

SelectElements:
    ('ALL'|distinct?='DISTINCT')? elements+=SelectElement (',' elements+=SelectElement)*
;
SelectElement infers SelectElement:
    {infer AllStar} '*'
    | {infer AllTable} variableName=[TableVariableSource:Identifier] '.' '*'
    | {infer ExpressionQuery} expr=Expression ('AS'? name=Identifier)?
;

2. FunctionCall also directly defines the OVER statement, which should probably only be in SimpleSelectStatement in a window function expression

Happy to propose a fix if I've understood this correctly.

Data types

Check the chapters 3 to 13 from the Standard:

• Numbers
• Bit strings
• Binary strings
• Characters
• Character strings
• Temporal values
• Boolean values
• Collections
• Row types
• Nulls
• Reference Types

Case When ...

Section within the standard

Example:

SELECT CASE
         WHEN team_name = 'Blue Bombers' THEN city
         ELSE '*********'
       END AS city
FROM Teams;

Basic type system

There are several type categories. With this issue, we will implement a basic type system that understands

• character strings
• numbers
  • integers
  • reals
• booleans

Each type has operators, casts to other types, assignment behaviors and functions that can be called.

Support for Sql Server dialect

Hi @Lotes,

Thanks for your part in creating this project - I'm considering including it in a project I work on - the current feature set is already very compelling.

I'm keen to add sql-server dialect support and thought it best to raise it here first in case contributing such a feature to this project is possible/preferable. I've been able to easily support sql-server's data types, but it seems syntax specific features (e.g square bracket for quoting keywords/spaces in table/column names) will require a separate / extended parser.

I've not tried the langium lib itself yet but have some experience building editor plugins using antlr4. Any pointers would be much appreciated.

Implement SELECT

SELECT arguments

• all-star column *
• all-table columns t.*
• See also expressions

FROM arguments

• table
• sub query
• joins

WHERE conditions

• See also expressions

GROUP BY clause

• TODO

ORDER BY clause

• TODO

HAVING clause

• TODO

LIMIT clause

• TODO

Expressions

• #4
• #5
• #6
• #7
• LIKE operator
• SIMILAR TO operator
• IS (NOT) operator
• sub query
• string concatenation operator
• SUBSTRING(str FROM from FOR length)
• boolean operators
• arithmetic operators
• relational operators