feat: Implement CONCAT_WS #2427
Conversation
|
|
src/expr/src/vector_op/concat_ws.rs
Outdated
| @@ -0,0 +1,97 @@ | |||
| // Copyright 2022 Singularity Data | |||
There was a problem hiding this comment.
WIP, this needs to be updated
src/sqlparser/src/ast/mod.rs
Outdated
| /// CONCAT_WS(SEP TEXT, STR "ANY" [, STR "ANY" [, ...] ]) | ||
| ConcatWs { | ||
| sep_expr: Box<Expr>, | ||
| string_exprs: Vec<Expr>, | ||
| }, |
There was a problem hiding this comment.
FYI we do not need to update the parser and add new variant / keyword for each new function. concat_ws(a, b, c) can be parsed as the general function call syntax. The variants here are for those with special syntax.
For example, substring(v1 from 2) needs special treatment because of the from, but substr(v1, 2) does not.
There was a problem hiding this comment.
To check my understanding: I should be parsing it into Expr::Function variant instead?
| @@ -107,6 +107,7 @@ impl FunctionCall { | |||
| Ok(DataType::Boolean) | |||
| } | |||
| ExprType::Coalesce => Ok(inputs[0].return_type()), | |||
| ExprType::ConcatWs => Ok(DataType::Varchar), // TODO: Validate input types, see below on how to recursively do so. | |||
There was a problem hiding this comment.
I should have left some comments here... The infer_type can only handle functions with a limited number of parameters, while the ones listed here (case-when, in-list, coalesce, concat) are all variadic.
To insert cast expr over all input expr to string/varchar, call cast_explicit on them.
- It can be a little bit confusing as the cast is actually implicit. But casting to varchar implicitly is disallowed in general cases and
concatis just special here. - As you may noticed in Tracking: Basic Built-in Functions #112, casting from another type to string has not been implemented in backend except for boolean.
|
Migrated over to #2470 for CI to run correctly. |
What's changed and what's your intention?
WIP, will fill these up later. #2405 , #112
Functioninsteadsrc/expr/expr_concat.ws.PLEASE DO NOT LEAVE THIS EMPTY !!!
Please explain IN DETAIL what the changes are in this PR and why they are needed:
Checklist
Refer to a related PR or issue link (optional)