From 183ddea5187eac83ec91f43a0c841f55937109e0 Mon Sep 17 00:00:00 2001
From: Nikita Vasilev <nekitvas@gmail.com>
Date: Sun, 13 Jan 2019 19:04:41 +0300
Subject: [PATCH] added parsing

---
 dbms/src/Parsers/ASTAlterQuery.cpp    | 20 +++++++++++++++++
 dbms/src/Parsers/ASTAlterQuery.h      | 12 ++++++++++
 dbms/src/Parsers/ParserAlterQuery.cpp | 32 +++++++++++++++++++++++++++
 3 files changed, 64 insertions(+)

diff --git a/dbms/src/Parsers/ASTAlterQuery.cpp b/dbms/src/Parsers/ASTAlterQuery.cpp
index c5cdf1475e3..893129a6f17 100644
--- a/dbms/src/Parsers/ASTAlterQuery.cpp
+++ b/dbms/src/Parsers/ASTAlterQuery.cpp
@@ -82,6 +82,26 @@ void ASTAlterCommand::formatImpl(
         settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str << "MODIFY ORDER BY " << (settings.hilite ? hilite_none : "");
         order_by->formatImpl(settings, state, frame);
     }
+    else if (type == ASTAlterCommand::ADD_INDEX)
+    {
+        settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str << "ADD INDEX " << (if_not_exists ? "IF NOT EXISTS " : "") << (settings.hilite ? hilite_none : "");
+        index_decl->formatImpl(settings, state, frame);
+
+        /// AFTER
+        if (index)
+        {
+            settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str << " AFTER " << (settings.hilite ? hilite_none : "");
+            index->formatImpl(settings, state, frame);
+        }
+        throw Exception("ADD/DROP INDEX is not implemented", ErrorCodes::LOGICAL_ERROR);
+    }
+    else if (type == ASTAlterCommand::DROP_INDEX)
+    {
+        settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str
+                      << "DROP INDEX " << (if_exists ? "IF EXISTS " : "") << (settings.hilite ? hilite_none : "");
+        index->formatImpl(settings, state, frame);
+        throw Exception("ADD/DROP INDEX is not implemented", ErrorCodes::LOGICAL_ERROR);
+    }
     else if (type == ASTAlterCommand::DROP_PARTITION)
     {
         settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str << (detach ? "DETACH" : "DROP") << " PARTITION "
diff --git a/dbms/src/Parsers/ASTAlterQuery.h b/dbms/src/Parsers/ASTAlterQuery.h
index a6759482a56..2c77e2031de 100644
--- a/dbms/src/Parsers/ASTAlterQuery.h
+++ b/dbms/src/Parsers/ASTAlterQuery.h
@@ -28,6 +28,9 @@ public:
         COMMENT_COLUMN,
         MODIFY_ORDER_BY,
 
+        ADD_INDEX,
+        DROP_INDEX,
+
         DROP_PARTITION,
         ATTACH_PARTITION,
         REPLACE_PARTITION,
@@ -58,6 +61,15 @@ public:
      */
     ASTPtr order_by;
 
+    /** The ADD INDEX query stores the IndexDeclaration there.
+     */
+    ASTPtr index_decl;
+
+    /** The ADD INDEX query stores the name of the index following AFTER.
+     *  The DROP INDEX query stores the name for deletion.
+     */
+     ASTPtr index;
+
     /** Used in DROP PARTITION and ATTACH PARTITION FROM queries.
      *  The value or ID of the partition is stored here.
      */
diff --git a/dbms/src/Parsers/ParserAlterQuery.cpp b/dbms/src/Parsers/ParserAlterQuery.cpp
index b17467ed365..7216453c364 100644
--- a/dbms/src/Parsers/ParserAlterQuery.cpp
+++ b/dbms/src/Parsers/ParserAlterQuery.cpp
@@ -5,6 +5,7 @@
 #include <Parsers/ParserCreateQuery.h>
 #include <Parsers/ParserPartition.h>
 #include <Parsers/ASTIdentifier.h>
+#include <Parsers/ASTIndexDeclaration.h>
 #include <Parsers/ASTAlterQuery.h>
 #include <Parsers/ASTLiteral.h>
 #include <Parsers/ASTAssignment.h>
@@ -26,6 +27,9 @@ bool ParserAlterCommand::parseImpl(Pos & pos, ASTPtr & node, Expected & expected
     ParserKeyword s_comment_column("COMMENT COLUMN");
     ParserKeyword s_modify_order_by("MODIFY ORDER BY");
 
+    ParserKeyword s_add_index("ADD INDEX");
+    ParserKeyword s_drop_index("DROP INDEX");
+
     ParserKeyword s_attach_partition("ATTACH PARTITION");
     ParserKeyword s_detach_partition("DETACH PARTITION");
     ParserKeyword s_drop_partition("DROP PARTITION");
@@ -50,6 +54,7 @@ bool ParserAlterCommand::parseImpl(Pos & pos, ASTPtr & node, Expected & expected
     ParserCompoundIdentifier parser_name;
     ParserStringLiteral parser_string_literal;
     ParserCompoundColumnDeclaration parser_col_decl;
+    ParserIndexDeclaration parser_idx_decl;
     ParserCompoundColumnDeclaration parser_modify_col_decl(false);
     ParserPartition parser_partition;
     ParserExpression parser_exp_elem;
@@ -91,6 +96,33 @@ bool ParserAlterCommand::parseImpl(Pos & pos, ASTPtr & node, Expected & expected
         command->type = ASTAlterCommand::DROP_COLUMN;
         command->detach = false;
     }
+    else if (s_add_index.ignore(pos, expected))
+    {
+        if (s_if_not_exists.ignore(pos, expected))
+            command->if_not_exists = true;
+
+        if (!parser_idx_decl.parse(pos, command->index_decl, expected))
+            return false;
+
+        if (s_after.ignore(pos, expected))
+        {
+            if (!parser_name.parse(pos, command->index, expected))
+                return false;
+        }
+
+        command->type = ASTAlterCommand::ADD_INDEX;
+    }
+    else if (s_drop_index.ignore(pos, expected))
+    {
+        if (s_if_exists.ignore(pos, expected))
+            command->if_exists = true;
+
+        if (!parser_name.parse(pos, command->index, expected))
+            return false;
+
+        command->type = ASTAlterCommand::DROP_INDEX;
+        command->detach = false;
+    }
     else if (s_clear_column.ignore(pos, expected))
     {
         if (s_if_exists.ignore(pos, expected))