diff --git a/src/backend/mysql.rs b/src/backend/mysql.rs
index 6db7474..b548b3a 100644
--- a/src/backend/mysql.rs
+++ b/src/backend/mysql.rs
@@ -86,11 +86,11 @@ impl SqlGenerator for MySql {
                         AutogenFunction::CurrentTimestamp => format!(" DEFAULT CURRENT_TIMESTAMP")
                     },
                     WrappedDefault::Null => format!(" DEFAULT NULL"),
-                    WrappedDefault::AnyText(ref val) => format!(" DEFAULT '{}'", val),
-                    WrappedDefault::UUID(ref val) => format!(" DEFAULT '{}'", val),
-                    WrappedDefault::Date(ref val) => format!(" DEFAULT '{:?}'", val),
+                    WrappedDefault::AnyText(ref val) => format!(" DEFAULT {}", val),
+                    WrappedDefault::UUID(ref val) => format!(" DEFAULT {}", val),
+                    WrappedDefault::Date(ref val) => format!(" DEFAULT {:?}", val),
                     WrappedDefault::Boolean(val) => format!(" DEFAULT {}", if *val { 1 } else { 0 }),
-                    WrappedDefault::Custom(ref val) => format!(" DEFAULT '{}'", val),
+                    WrappedDefault::Custom(ref val) => format!(" DEFAULT {}", val),
                     _ => format!(" DEFAULT {}", m),
                 },
                 _ => format!(""),
diff --git a/src/backend/pg.rs b/src/backend/pg.rs
index d309bda..1fa2a49 100644
--- a/src/backend/pg.rs
+++ b/src/backend/pg.rs
@@ -88,10 +88,10 @@ impl SqlGenerator for Pg {
                         AutogenFunction::CurrentTimestamp => format!(" DEFAULT CURRENT_TIMESTAMP")
                     }
                     WrappedDefault::Null => format!(" DEFAULT NULL"),
-                    WrappedDefault::AnyText(ref val) => format!(" DEFAULT '{}'", val),
-                    WrappedDefault::UUID(ref val) => format!(" DEFAULT '{}'", val),
-                    WrappedDefault::Date(ref val) => format!(" DEFAULT '{:?}'", val),
-                    WrappedDefault::Custom(ref val) => format!(" DEFAULT '{}'", val),
+                    WrappedDefault::AnyText(ref val) => format!(" DEFAULT {}", val),
+                    WrappedDefault::UUID(ref val) => format!(" DEFAULT {}", val),
+                    WrappedDefault::Date(ref val) => format!(" DEFAULT {:?}", val),
+                    WrappedDefault::Custom(ref val) => format!(" DEFAULT {}", val),
                     _ => format!(" DEFAULT {}", m)
                 },
                 _ => format!(""),
diff --git a/src/backend/sqlite3.rs b/src/backend/sqlite3.rs
index 178dbc8..50006ad 100644
--- a/src/backend/sqlite3.rs
+++ b/src/backend/sqlite3.rs
@@ -84,11 +84,11 @@ impl SqlGenerator for Sqlite {
                         AutogenFunction::CurrentTimestamp => format!(" DEFAULT CURRENT_TIMESTAMP")
                     }
                     WrappedDefault::Null => format!(" DEFAULT NULL"),
-                    WrappedDefault::AnyText(ref val) => format!(" DEFAULT '{}'", val),
-                    WrappedDefault::UUID(ref val) => format!(" DEFAULT '{}'", val),
-                    WrappedDefault::Date(ref val) => format!(" DEFAULT '{:?}'", val),
+                    WrappedDefault::AnyText(ref val) => format!(" DEFAULT {}", val),
+                    WrappedDefault::UUID(ref val) => format!(" DEFAULT {}", val),
+                    WrappedDefault::Date(ref val) => format!(" DEFAULT {:?}", val),
                     WrappedDefault::Boolean(val) => format!(" DEFAULT {}", if *val { 1 } else { 0 }),
-                    WrappedDefault::Custom(ref val) => format!(" DEFAULT '{}'", val),
+                    WrappedDefault::Custom(ref val) => format!(" DEFAULT {}", val),
                     _ => format!(" DEFAULT {}", m)
                 },
                 _ => format!(""),