Remove #tables extra args again

This issue was resolved by #21687 already. But re-add args by #18856.
`#tables` extra args was only using by `#table_exists?`. This is for
internal API. This commit will remove these extra args again.

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -482,16 +482,11 @@ module ActiveRecord
         show_variable 'collation_database'
       end
 
-      def tables(name = nil, database = nil, like = nil) #:nodoc:
-        database ||= current_database
-
+      def tables(name = nil) # :nodoc:
         sql = "SELECT table_name FROM information_schema.tables "
-        sql << "WHERE table_schema = #{quote(database)}"
-        sql << " AND table_name = #{quote(like)}" if like
+        sql << "WHERE table_schema = #{quote(@config[:database])}"
 
-        execute_and_free(sql, 'SCHEMA') do |result|
-          result.collect(&:first)
-        end
+        select_values(sql, 'SCHEMA')
       end
       alias data_sources tables
 

activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb

@@ -311,22 +311,18 @@ module ActiveRecord
 
       # SCHEMA STATEMENTS ========================================
 
-      def tables(name = nil, table_name = nil) #:nodoc:
-        sql = <<-SQL
-          SELECT name
-          FROM sqlite_master
-          WHERE (type = 'table' OR type = 'view') AND NOT name = 'sqlite_sequence'
-        SQL
-        sql << " AND name = #{quote_table_name(table_name)}" if table_name
-
-        exec_query(sql, 'SCHEMA').map do |row|
-          row['name']
-        end
+      def tables(name = nil) # :nodoc:
+        select_values("SELECT name FROM sqlite_master WHERE type IN ('table','view') AND name <> 'sqlite_sequence'", 'SCHEMA')
       end
       alias data_sources tables
 
       def table_exists?(table_name)
-        table_name && tables(nil, table_name).any?
+        return false unless table_name.present?
+
+        sql = "SELECT name FROM sqlite_master WHERE type IN ('table','view') AND name <> 'sqlite_sequence'"
+        sql << " AND name = #{quote(table_name)}"
+
+        select_values(sql, 'SCHEMA').any?
       end
       alias data_source_exists? table_exists?
 

activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb

@@ -294,7 +294,7 @@ module ActiveRecord
       def test_tables_logs_name
         sql = <<-SQL
           SELECT name FROM sqlite_master
-          WHERE (type = 'table' OR type = 'view') AND NOT name = 'sqlite_sequence'
+          WHERE type IN ('table','view') AND name <> 'sqlite_sequence'
         SQL
         assert_logged [[sql.squish, 'SCHEMA', []]] do
           @conn.tables('hello')
@@ -313,8 +313,7 @@ module ActiveRecord
         with_example_table do
           sql = <<-SQL
             SELECT name FROM sqlite_master
-            WHERE (type = 'table' OR type = 'view')
-            AND NOT name = 'sqlite_sequence' AND name = \"ex\"
+            WHERE type IN ('table','view') AND name <> 'sqlite_sequence' AND name = 'ex'
           SQL
           assert_logged [[sql.squish, 'SCHEMA', []]] do
             assert @conn.table_exists?('ex')

activerecord/test/cases/test_case.rb

@@ -103,7 +103,7 @@ module ActiveRecord
     # ignored SQL, or better yet, use a different notification for the queries
     # instead examining the SQL content.
     oracle_ignored     = [/^select .*nextval/i, /^SAVEPOINT/, /^ROLLBACK TO/, /^\s*select .* from all_triggers/im, /^\s*select .* from all_constraints/im, /^\s*select .* from all_tab_cols/im]
-    mysql_ignored      = [/^SHOW FULL TABLES/i, /^SHOW FULL FIELDS/, /^SHOW CREATE TABLE /i, /^SHOW VARIABLES /, /^SELECT DATABASE\(\) as db$/, /^\s*SELECT (?:column_name|table_name)\b.*\bFROM information_schema\.(?:key_column_usage|tables)\b/im]
+    mysql_ignored      = [/^SHOW FULL TABLES/i, /^SHOW FULL FIELDS/, /^SHOW CREATE TABLE /i, /^SHOW VARIABLES /, /^\s*SELECT (?:column_name|table_name)\b.*\bFROM information_schema\.(?:key_column_usage|tables)\b/im]
     postgresql_ignored = [/^\s*select\b.*\bfrom\b.*pg_namespace\b/im, /^\s*select tablename\b.*from pg_tables\b/im, /^\s*select\b.*\battname\b.*\bfrom\b.*\bpg_attribute\b/im, /^SHOW search_path/i]
     sqlite3_ignored =    [/^\s*SELECT name\b.*\bFROM sqlite_master/im, /^\s*SELECT sql\b.*\bFROM sqlite_master/im]