Revert "Normalize backtick SQL for PostgreSQL"

This reverts commit 395cede.

Author: antarr

gems/mysql_genius-core/lib/mysql_genius/core/query_explainer.rb

@@ -32,7 +32,7 @@ def explain(sql, skip_validation: false)
           raise QueryRunner::Rejected, error if error
         end
 
-        clean_sql = SqlValidator.normalize_identifier_quotes(sql, @connection).gsub(/;\s*\z/, "")
+        clean_sql = sql.gsub(/;\s*\z/, "")
 
         unless looks_complete?(clean_sql)
           raise Truncated, "This query appears to be truncated and cannot be explained."

gems/mysql_genius-core/lib/mysql_genius/core/query_runner.rb

@@ -35,8 +35,7 @@ def run(sql, row_limit:)
         )
         raise Rejected, validation_error if validation_error
 
-        normalized = SqlValidator.normalize_identifier_quotes(sql, @connection)
-        limited = SqlValidator.apply_row_limit(normalized, row_limit)
+        limited = SqlValidator.apply_row_limit(sql, row_limit)
         timed = apply_timeout_hint(limited)
 
         start = Process.clock_gettime(Process::CLOCK_MONOTONIC)

gems/mysql_genius-core/lib/mysql_genius/core/sql_validator.rb

@@ -54,87 +54,13 @@ def apply_row_limit(sql, limit)
         end
       end
 
-      def normalize_identifier_quotes(sql, connection)
-        quote = connection.quote_table_name("mysql_genius_identifier_probe")[0]
-        return sql if quote == "`" || !sql.include?("`")
-
-        rewrite_backtick_identifiers(sql, connection)
-      end
-
       def masked_column?(column_name, patterns)
         patterns.any? { |pattern| column_name.downcase.include?(pattern) }
       end
 
       def unquote_identifier(parts)
         (parts.find { |part| part && !part.empty? } || "").gsub('""', '"')
       end
-
-      def rewrite_backtick_identifiers(sql, connection)
-        output = +""
-        i = 0
-
-        while i < sql.length
-          char = sql[i]
-
-          if char == "'"
-            literal, i = read_single_quoted_literal(sql, i)
-            output << literal
-          elsif char == "`"
-            identifier, i = read_backtick_identifier(sql, i)
-            output << connection.quote_table_name(identifier)
-          else
-            output << char
-            i += 1
-          end
-        end
-
-        output
-      end
-
-      def read_single_quoted_literal(sql, index)
-        output = +"'"
-        i = index + 1
-
-        while i < sql.length
-          output << sql[i]
-          if sql[i] == "'"
-            if sql[i + 1] == "'"
-              output << sql[i + 1]
-              i += 2
-              next
-            end
-
-            i += 1
-            break
-          end
-          i += 1
-        end
-
-        [output, i]
-      end
-
-      def read_backtick_identifier(sql, index)
-        output = +""
-        i = index + 1
-
-        while i < sql.length
-          if sql[i] == "`"
-            if sql[i + 1] == "`"
-              output << "`"
-              i += 2
-              next
-            end
-
-            i += 1
-            break
-          end
-
-          output << sql[i]
-          i += 1
-        end
-
-        [output, i]
-      end
     end
   end
 end

gems/mysql_genius-core/spec/mysql_genius/core/query_explainer_spec.rb

@@ -85,19 +85,5 @@
       explainer.explain("SELECT id FROM users;")
       expect(captured_sql).to(eq("EXPLAIN SELECT id FROM users"))
     end
-
-    it "rewrites backtick identifiers when the connection uses double quotes" do
-      captured_sql = nil
-      allow(connection).to(receive(:quote_table_name) { |name| %("#{name}") })
-      connection.stub_query(/EXPLAIN/, columns: ["id"], rows: [[1]])
-      allow(connection).to(receive(:exec_query).and_wrap_original do |original, sql, **kwargs|
-        captured_sql = sql
-        original.call(sql, **kwargs)
-      end)
-
-      explainer.explain("SELECT `id` FROM `users`")
-
-      expect(captured_sql).to(eq(%(EXPLAIN SELECT "id" FROM "users")))
-    end
   end
 end

gems/mysql_genius-core/spec/mysql_genius/core/query_runner_spec.rb

@@ -63,20 +63,6 @@
       expect(captured_sql).to(match(/LIMIT 25/))
     end
 
-    it "rewrites backtick identifiers when the connection uses double quotes" do
-      captured_sql = nil
-      allow(connection).to(receive(:quote_table_name) { |name| %("#{name}") })
-      connection.stub_query(/SELECT/, columns: ["id"], rows: [[1]])
-      allow(connection).to(receive(:exec_query).and_wrap_original do |original, sql, **kwargs|
-        captured_sql = sql
-        original.call(sql, **kwargs)
-      end)
-
-      runner.run("SELECT `id` FROM `users`", row_limit: 25)
-
-      expect(captured_sql).to(include(%("id" FROM "users")))
-    end
-
     it "masks columns matching configured patterns with [REDACTED]" do
       connection.stub_query(
         /SELECT/,

gems/mysql_genius-core/spec/mysql_genius/core/sql_validator_spec.rb

@@ -4,7 +4,7 @@
   let(:blocked_tables) { ["sessions", "authentication_tokens"] }
   let(:all_tables) { ["users", "posts", "sessions", "authentication_tokens"] }
   let(:connection) do
-    double("connection", tables: all_tables, quote_table_name: "`mysql_genius_identifier_probe`")
+    double("connection", tables: all_tables)
   end
 
   def validate(sql)
@@ -116,32 +116,6 @@ def validate(sql)
     end
   end
 
-  describe ".normalize_identifier_quotes" do
-    it "leaves backticks intact for backtick-quoting adapters" do
-      sql = "SELECT `id` FROM `users` WHERE `name` = 'has `backtick` text'"
-
-      expect(described_class.normalize_identifier_quotes(sql, connection)).to(eq(sql))
-    end
-
-    it "rewrites backtick identifiers for double-quote adapters" do
-      pg_connection = double("connection")
-      allow(pg_connection).to(receive(:quote_table_name) { |name| %("#{name.gsub('"', '""')}") })
-
-      sql = "SELECT `id`, `title` FROM `users` WHERE `name` = 'has `backtick` text'"
-
-      expect(described_class.normalize_identifier_quotes(sql, pg_connection))
-        .to(eq(%(SELECT "id", "title" FROM "users" WHERE "name" = 'has `backtick` text')))
-    end
-
-    it "unescapes doubled backticks before adapter quoting" do
-      pg_connection = double("connection")
-      allow(pg_connection).to(receive(:quote_table_name) { |name| %("#{name.gsub('"', '""')}") })
-
-      expect(described_class.normalize_identifier_quotes("SELECT `weird``name` FROM `users`", pg_connection))
-        .to(eq(%(SELECT "weird`name" FROM "users")))
-    end
-  end
-
   describe ".masked_column?" do
     let(:patterns) { ["password", "secret", "digest", "token"] }