diff --git a/src/DIRAC/RequestManagementSystem/DB/RequestDB.py b/src/DIRAC/RequestManagementSystem/DB/RequestDB.py
index 126771ffcca..701676fde22 100644
--- a/src/DIRAC/RequestManagementSystem/DB/RequestDB.py
+++ b/src/DIRAC/RequestManagementSystem/DB/RequestDB.py
@@ -39,7 +39,7 @@
     String,
     DateTime,
     Enum,
-    BLOB,
+    TEXT,
     BigInteger,
     distinct,
 )
@@ -100,7 +100,7 @@
     Column("TargetSE", String(255)),
     Column("CreationTime", DateTime),
     Column("SourceSE", String(255)),
-    Column("Arguments", BLOB),
+    Column("Arguments", TEXT),
     Column("Error", String(255)),
     Column("Type", String(64), nullable=False),
     Column("Order", Integer, nullable=False),
@@ -158,7 +158,7 @@
     Column("OwnerGroup", String(32)),
     Column("SubmitTime", DateTime),
     Column("RequestID", Integer, primary_key=True),
-    Column("SourceComponent", BLOB),
+    Column("SourceComponent", String(255)),
     Column("NotBefore", DateTime),
     mysql_engine="InnoDB",
 )