diff --git a/geocoder/admin0/sql/indexes.sql b/geocoder/admin0/sql/indexes.sql
new file mode 100644
index 0000000..90bf8b2
--- /dev/null
+++ b/geocoder/admin0/sql/indexes.sql
@@ -0,0 +1,8 @@
+-- create indexes on synonyms table
+CREATE INDEX idx_admin0_synonyms_name_ ON admin0_synonyms (name_);
+CREATE INDEX idx_admin0_synonyms_rank ON admin0_synonyms (rank);
+CREATE INDEX idx_admin0_synonyms_name_rank ON admin0_synonyms (name_, rank);
+
+-- create indexes on polygon table
+CREATE INDEX idx_ne_admin0_v3_adm0_a3 ON ne_admin0_v3 (adm0_a3);
+
diff --git a/geocoder/admin0/sql/triggers.sql b/geocoder/admin0/sql/triggers.sql
new file mode 100644
index 0000000..1bc4880
--- /dev/null
+++ b/geocoder/admin0/sql/triggers.sql
@@ -0,0 +1,17 @@
+-- create trigger function. used in both admin1 and admin2 synonym tables
+CREATE OR REPLACE FUNCTION alpha_numeric_identifiers() RETURNS trigger AS $alpha_numeric_identifiers$
+    BEGIN
+        NEW.name_ := lower(regexp_replace(NEW.name, '[^A-z\u00C0-\u00ff]+', '', 'g'));
+        RETURN NEW;
+    END;
+$alpha_numeric_identifiers$ LANGUAGE plpgsql;
+
+-- add trigger on admin0 synonym table name_ column
+CREATE TRIGGER admin0_synonyms_name_update
+BEFORE INSERT OR UPDATE OF name ON admin0_synonyms 
+  FOR EACH ROW EXECUTE PROCEDURE alpha_numeric_identifiers()
+
+-- add trigger on admin1 synonym table name_ column
+CREATE TRIGGER admin1_synonyms_name_update
+BEFORE INSERT OR UPDATE OF name ON admin1_synonyms 
+  FOR EACH ROW EXECUTE PROCEDURE alpha_numeric_identifiers()
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