diff --git a/sql/patch_65_66_b.sql b/sql/patch_65_66_b.sql
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index 0000000000000000000000000000000000000000..014fb5010a8bba78dde53d1ad8fff7b8b2503504
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+# patch_65_66_b.sql
+#
+# Title: Make external_db.external_db_id AUTO_INCREMENT and INTEGER UNSIGNED.
+#
+# Description:
+# We're using too high values in external_db.external_db_id for the
+# current SMALLINT, and with the web interface we're using internally
+# to add new entries, we also need this field to be AUTO_INCREMENT.
+
+ALTER TABLE external_db
+  MODIFY external_db_id INTEGER UNSIGNED NOT NULL AUTO_INCREMENT;
+
+# Also modify this field in the other tables that uses it as a foreign key:
+ALTER TABLE dna_align_feature       MODIFY external_db_id INTEGER UNSIGNED;
+ALTER TABLE protein_align_feature   MODIFY external_db_id INTEGER UNSIGNED;
+ALTER TABLE seq_region_synonym      MODIFY external_db_id INTEGER UNSIGNED;
+ALTER TABLE unmapped_object         MODIFY external_db_id INTEGER UNSIGNED;
+ALTER TABLE xref                    MODIFY external_db_id INTEGER UNSIGNED;
+
+# Patch identifier:
+INSERT INTO meta (species_id, meta_key, meta_value)
+  VALUES (NULL, 'patch', 'patch_65_66_b.sql|fix_external_db_id');