From 5bbc32c896fc032dd38d273e86f070c44df53aad Mon Sep 17 00:00:00 2001
From: AlexMiroshnikov <ilexicy@gmail.com>
Date: Sun, 8 May 2022 12:42:59 +0200
Subject: [PATCH] DBZ-4780 Introduce support of LATERAL operator

---
 .../ddl/parser/mysql/generated/MySqlLexer.g4   |  1 +
 .../ddl/parser/mysql/generated/MySqlParser.g4  | 10 ++++++++--
 .../resources/mysql/examples/ddl_create.sql    |  7 +++++++
 .../resources/mysql/examples/dml_select.sql    | 18 +++++++++++++++++-
 4 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlLexer.g4 b/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlLexer.g4
index 8f44dbbfa..de42f6a45 100644
--- a/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlLexer.g4
+++ b/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlLexer.g4
@@ -131,6 +131,7 @@ JOIN:                                'JOIN';
 KEY:                                 'KEY';
 KEYS:                                'KEYS';
 KILL:                                'KILL';
+LATERAL:                             'LATERAL';
 LEADING:                             'LEADING';
 LEAVE:                               'LEAVE';
 LEFT:                                'LEFT';
diff --git a/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlParser.g4 b/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlParser.g4
index 6c8eacbc5..c19286a7f 100644
--- a/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlParser.g4
+++ b/debezium-ddl-parser/src/main/antlr4/io/debezium/ddl/parser/mysql/generated/MySqlParser.g4
@@ -881,6 +881,7 @@ selectStatement
           queryExpression
         )?
         orderByClause? limitClause? lockClause?                     #unionParenthesisSelect
+    | querySpecificationNointo (',' lateralStatement)+              #withLateralStatement
     ;
 
 updateStatement
@@ -1006,13 +1007,13 @@ indexHintType
     ;
 
 joinPart
-    : (INNER | CROSS)? JOIN tableSourceItem
+    : (INNER | CROSS)? JOIN LATERAL? tableSourceItem
       (
         ON expression
         | USING '(' uidList ')'
       )?                                                            #innerJoin
     | STRAIGHT_JOIN tableSourceItem (ON expression)?                #straightJoin
-    | (LEFT | RIGHT) OUTER? JOIN tableSourceItem
+    | (LEFT | RIGHT) OUTER? JOIN LATERAL? tableSourceItem
         (
           ON expression
           | USING '(' uidList ')'
@@ -1053,6 +1054,11 @@ unionStatement
       (querySpecificationNointo | queryExpressionNointo)
     ;
 
+lateralStatement
+    : LATERAL (querySpecificationNointo | queryExpressionNointo)
+    | LATERAL '(' (querySpecificationNointo | queryExpressionNointo) ')' (AS? uid)?
+    ;
+
 // details
 
 selectSpec
diff --git a/debezium-ddl-parser/src/test/resources/mysql/examples/ddl_create.sql b/debezium-ddl-parser/src/test/resources/mysql/examples/ddl_create.sql
index 4b3816df4..ff87b846e 100644
--- a/debezium-ddl-parser/src/test/resources/mysql/examples/ddl_create.sql
+++ b/debezium-ddl-parser/src/test/resources/mysql/examples/ddl_create.sql
@@ -475,3 +475,10 @@ WITH RECURSIVE cte (n) AS
 )
 SELECT * FROM cte;
 #end
+
+#begin
+CREATE VIEW `invoice_payments_stats` AS
+SELECT
+    `i`.`id` AS `id`
+FROM (`invoices` `i` JOIN lateral (SELECT MAX(`ip`.`date`) AS `latest_payment` FROM `invoice_payments` `ip`) `ps`);
+#end
diff --git a/debezium-ddl-parser/src/test/resources/mysql/examples/dml_select.sql b/debezium-ddl-parser/src/test/resources/mysql/examples/dml_select.sql
index a91935533..86f31668f 100644
--- a/debezium-ddl-parser/src/test/resources/mysql/examples/dml_select.sql
+++ b/debezium-ddl-parser/src/test/resources/mysql/examples/dml_select.sql
@@ -194,4 +194,20 @@ SELECT
     GROUP_CONCAT(bin_volume order by id) AS `rank`
 FROM table2
     WINDOW w AS (PARTITION BY id, bin_volume ORDER BY id ROWS UNBOUNDED PRECEDING),
-           w2 AS (PARTITION BY id, bin_volume ORDER BY id DESC ROWS 10 PRECEDING);
\ No newline at end of file
+           w2 AS (PARTITION BY id, bin_volume ORDER BY id DESC ROWS 10 PRECEDING);
+
+#begin
+-- https://dev.mysql.com/doc/refman/8.0/en/lateral-derived-tables.html
+SELECT
+  salesperson.name,
+  max_sale.amount,
+  max_sale.customer_name
+FROM
+  salesperson,
+  LATERAL
+  (SELECT amount, customer_name
+    FROM all_sales
+    WHERE all_sales.salesperson_id = salesperson.id
+    ORDER BY amount DESC LIMIT 1)
+  AS max_sale;
+#end