From e5b15bf93f36a974500a470847e611e019205cde Mon Sep 17 00:00:00 2001
From: simon petit <nomisp96@hotmail.fr>
Date: Mon, 25 Nov 2024 10:36:33 +0000
Subject: [PATCH] Allowing cascading joins
---
lib/ast.ml | 19 +++++++++++--
parser/parser.mly | 70 +++++++++++++++++++++++-----------------------
test/SQL_parser.ml | 46 ++++++++++++++++++++++++++++--
3 files changed, 96 insertions(+), 39 deletions(-)
diff --git a/lib/ast.ml b/lib/ast.ml
index 3f37dc3..5debe2f 100644
--- a/lib/ast.ml
+++ b/lib/ast.ml
@@ -6,7 +6,7 @@ and column =
| Column of string
and table =
| Table of string
- | Join of table * join_type * table
+ | Join of table * join_type * table * condition option
and join_type =
| Inner
| Left
@@ -15,4 +15,19 @@ and join_type =
| Cross
| Union
| Natural
-
+and condition =
+ | Condition of string * comparison
+ | And of condition * condition
+ | Or of condition * condition
+ | Not of condition
+and comparison =
+ | Comparison of operator * string
+and operator =
+ | Equals
+ | NotEquals
+ | LessThan
+ | GreaterThan
+ | LessEquals
+ | GreaterEquals
+and search_condition =
+ | Search of string
diff --git a/parser/parser.mly b/parser/parser.mly
index 2f2afc9..184c70b 100644
--- a/parser/parser.mly
+++ b/parser/parser.mly
@@ -53,7 +53,6 @@ table_reference :
(* | table_primary_or_joined_table sample_clause { $1 } *)
table_primary_or_joined_table:
- (* | table_primary { Table($1) }*)
| table_primary { $1 }
| joined_table { $1 }
@@ -70,24 +69,24 @@ joined_table :
| union_join { $1 }
cross_join:
- | table_reference CROSS JOIN table_primary { Join($1, Cross, $4) }
+ | table_reference CROSS JOIN table_primary { Join($1, Cross, $4, None) }
qualified_join:
- | table_reference JOIN table_reference join_specification { Join($1, Left, $3) }
- | table_reference join_type JOIN table_reference join_specification { Join($1, $2, $4) }
+ | table_reference JOIN table_reference join_specification { Join($1, Left, $3, $4) }
+ | table_reference join_type JOIN table_reference join_specification { Join($1, $2, $4, $5) }
join_specification:
- | join_condition {}
+ | join_condition { $1 }
join_condition:
- | ON search_condition {}
+ | ON search_condition { Some($2) }
natural_join:
- | table_reference NATURAL JOIN table_primary { Join($1, Natural, $4) }
- | table_reference NATURAL join_type JOIN table_primary { Join($1, Natural, $5) }
+ | table_reference NATURAL JOIN table_primary { Join($1, Natural, $4, None) }
+ | table_reference NATURAL join_type JOIN table_primary { Join($1, Natural, $5, None) }
union_join:
- | table_reference UNION JOIN table_primary { Join($1,Union, $4) }
+ | table_reference UNION JOIN table_primary { Join($1, Union, $4, None) }
table_name :
| IDENT { Table($1) }
@@ -107,43 +106,44 @@ where_clause :
| WHERE search_condition { }
search_condition:
- | IDENT EQUALS_OPERATOR IDENT {}
+ (*| IDENT EQUALS_OPERATOR IDENT {}*)
+ | boolean_value_expression { $1 }
boolean_value_expression:
- | boolean_term {}
- | boolean_value_expression OR boolean_term {}
+ | boolean_term { $1 }
+ | boolean_value_expression OR boolean_term { Or($1, $3) }
boolean_term:
- | boolean_factor {}
- | boolean_term AND boolean_factor {}
+ | boolean_factor { $1 }
+ | boolean_term AND boolean_factor { And($1, $3) }
boolean_factor:
- | boolean_test {}
- | NOT boolean_test {}
+ | boolean_test { $1 }
+ | NOT boolean_test { Not($2) }
boolean_test:
- | boolean_primary {}
+ | boolean_primary { $1 }
boolean_primary :
- | predicate {}
- | boolean_predicand {}
+ | predicate { $1 }
+ (*| boolean_predicand {}*)
predicate :
- | comparison_predicate {}
+ | comparison_predicate { $1 }
comparison_predicate :
- | row_value_predicand comparison_predicate_part2 {}
+ | row_value_predicand comparison_predicate_part2 { Condition($1, $2) }
comparison_predicate_part2:
- | comp_op row_value_predicand {}
+ | comp_op row_value_predicand { Comparison($1, $2) }
comp_op :
- | EQUALS_OPERATOR {}
- | not_equals_operator {}
- | LESS_THAN_OPERATOR {}
- | GREATER_THAN_OPERATOR {}
- | less_than_or_equals_operator {}
- | greater_than_or_equals_operator {}
+ | EQUALS_OPERATOR { Equals }
+ | not_equals_operator { NotEquals }
+ | LESS_THAN_OPERATOR { LessThan }
+ | GREATER_THAN_OPERATOR { GreaterThan }
+ | less_than_or_equals_operator { LessEquals }
+ | greater_than_or_equals_operator { GreaterEquals }
not_equals_operator :
| LESS_THAN_OPERATOR GREATER_THAN_OPERATOR {}
@@ -155,23 +155,23 @@ greater_than_or_equals_operator:
| GREATER_THAN_OPERATOR EQUALS_OPERATOR {}
row_value_predicand:
- | row_value_special_case {}
+ | row_value_special_case { $1 }
row_value_special_case :
- | nonparenthesized_value_expression_primary {}
+ | nonparenthesized_value_expression_primary { $1 }
nonparenthesized_value_expression_primary:
- | column_reference {}
+ | column_reference { $1 }
column_reference:
- | basic_identifier_chain {}
+ | basic_identifier_chain { $1 }
basic_identifier_chain:
- | identifier_chain {}
+ | identifier_chain { $1 }
identifier_chain:
- | IDENT {}
- | identifier_chain DOT IDENT {}
+ | IDENT { $1 }
+ (*| identifier_chain DOT IDENT {}*)
boolean_predicand:
| nonparenthesized_value_expression_primary {}
diff --git a/test/SQL_parser.ml b/test/SQL_parser.ml
index a09f19c..eb1d4c3 100644
--- a/test/SQL_parser.ml
+++ b/test/SQL_parser.ml
@@ -7,5 +7,47 @@ let parse query =
let () =
assert(parse "SELECT ab FROM b1" = Query(Select([Column("ab")], [Table "b1"])));
assert(parse "SELECT * FROM b1" = Query(Select([Asterisk], [Table "b1"])));
- assert(parse "SELECT * FROM t1 CROSS JOIN t2" = Query(Select([Asterisk], [Join(Table("t1"), Cross, Table("t2"))])));
- assert(parse "SELECT * FROM t1 JOIN t2 ON a = b" = Query(Select([Asterisk], [Join(Table("t1"), Left, Table("t2"))])));
+ assert(parse "SELECT * FROM t1 CROSS JOIN t2" = Query(Select([Asterisk], [Join(Table("t1"), Cross, Table("t2"), None)])));
+ assert(parse "SELECT * FROM t1 JOIN t2 ON a = b" = Query(
+ Select([Asterisk], [
+ Join(
+ Table("t1"),
+ Left,
+ Table("t2"),
+ Some(
+ Condition(
+ "a",
+ Comparison(Equals, "b")
+ )
+ )
+ )
+ ]
+ )
+ ));
+ assert(parse "SELECT * FROM t1 JOIN t2 ON a = b JOIN t3 ON c = d" = Query(
+ Select([Asterisk], [
+ Join(
+ Join(
+ Table("t1"),
+ Left,
+ Table("t2"),
+ Some(
+ Condition(
+ "a",
+ Comparison(Equals, "b")
+ )
+ )
+ ),
+ Left,
+ Table("t3"),
+ Some(
+ Condition(
+ "c",
+ Comparison(Equals, "d")
+ )
+ )
+ )
+ ]
+ )
+ )
+ );