Remove dead MySQL code

None of this code can be reached any more, so it can all be removed

1 files changed, 21 insertions, 55 deletions

diff --git a/lib/gitlab/database.rb b/lib/gitlab/database.rb
index 3e4c720b49a..eef63536de4 100644
--- a/lib/gitlab/database.rb
+++ b/lib/gitlab/database.rb
@@ -4,13 +4,13 @@ module Gitlab
   module Database
     include Gitlab::Metrics::Methods
 
-    # The max value of INTEGER type is the same between MySQL and PostgreSQL:
     # https://www.postgresql.org/docs/9.2/static/datatype-numeric.html
-    # http://dev.mysql.com/doc/refman/5.7/en/integer-types.html
     MAX_INT_VALUE = 2147483647
+
     # The max value between MySQL's TIMESTAMP and PostgreSQL's timestampz:
     # https://www.postgresql.org/docs/9.1/static/datatype-datetime.html
     # https://dev.mysql.com/doc/refman/5.7/en/datetime.html
+    # FIXME: this should just be the max value of timestampz
     MAX_TIMESTAMP_VALUE = Time.at((1 << 31) - 1).freeze
 
     # Minimum schema version from which migrations are supported
@@ -39,11 +39,11 @@ module Gitlab
     end
 
     def self.human_adapter_name
-      postgresql? ? 'PostgreSQL' : 'MySQL'
-    end
-
-    def self.mysql?
-      adapter_name.casecmp('mysql2').zero?
+      if postgresql?
+        'PostgreSQL'
+      else
+        'Unknown'
+      end
     end
 
     def self.postgresql?
@@ -60,15 +60,14 @@ module Gitlab
 
     # Check whether the underlying database is in read-only mode
     def self.db_read_only?
-      if postgresql?
-        pg_is_in_recovery =
-          ActiveRecord::Base.connection.execute('SELECT pg_is_in_recovery()')
-            .first.fetch('pg_is_in_recovery')
+      pg_is_in_recovery =
+        ActiveRecord::Base
+          .connection
+          .execute('SELECT pg_is_in_recovery()')
+          .first
+          .fetch('pg_is_in_recovery')
 
-        Gitlab::Utils.to_boolean(pg_is_in_recovery)
-      else
-        false
-      end
+      Gitlab::Utils.to_boolean(pg_is_in_recovery)
     end
 
     def self.db_read_write?
@@ -118,51 +117,23 @@ module Gitlab
     end
 
     def self.nulls_last_order(field, direction = 'ASC')
-      order = "#{field} #{direction}"
-
-      if postgresql?
-        order = "#{order} NULLS LAST"
-      else
-        # `field IS NULL` will be `0` for non-NULL columns and `1` for NULL
-        # columns. In the (default) ascending order, `0` comes first.
-        order = "#{field} IS NULL, #{order}" if direction == 'ASC'
-      end
-
-      Arel.sql(order)
+      Arel.sql("#{field} #{direction} NULLS LAST")
     end
 
     def self.nulls_first_order(field, direction = 'ASC')
-      order = "#{field} #{direction}"
-
-      if postgresql?
-        order = "#{order} NULLS FIRST"
-      else
-        # `field IS NULL` will be `0` for non-NULL columns and `1` for NULL
-        # columns. In the (default) ascending order, `0` comes first.
-        order = "#{field} IS NULL, #{order}" if direction == 'DESC'
-      end
-
-      Arel.sql(order)
+      Arel.sql("#{field} #{direction} NULLS FIRST")
     end
 
     def self.random
-      postgresql? ? "RANDOM()" : "RAND()"
+      "RANDOM()"
     end
 
     def self.true_value
-      if postgresql?
-        "'t'"
-      else
-        1
-      end
+      "'t'"
     end
 
     def self.false_value
-      if postgresql?
-        "'f'"
-      else
-        0
-      end
+      "'f'"
     end
 
     def self.with_connection_pool(pool_size)
@@ -182,7 +153,7 @@ module Gitlab
     # rows - An Array of Hash instances, each mapping the columns to their
     #        values.
     # return_ids - When set to true the return value will be an Array of IDs of
-    #              the inserted rows, this only works on PostgreSQL.
+    #              the inserted rows
     # disable_quote - A key or an Array of keys to exclude from quoting (You
     #                 become responsible for protection from SQL injection for
     #                 these keys!)
@@ -191,7 +162,6 @@ module Gitlab
 
       keys = rows.first.keys
       columns = keys.map { |key| connection.quote_column_name(key) }
-      return_ids = false if mysql?
 
       disable_quote = Array(disable_quote).to_set
       tuples = rows.map do |row|
@@ -258,11 +228,7 @@ module Gitlab
     def self.database_version
       row = connection.execute("SELECT VERSION()").first
 
-      if postgresql?
-        row['version']
-      else
-        row.first
-      end
+      row['version']
     end
 
     private_class_method :database_version