Refactorings

- shorten the index name. similar name pattern then existing idexes
- changed order of index. indentity_zone_id should be always first column
- removed not null from SQL, since not needed, see https://stackoverflow.com/questions/8660203/how-to-check-for-is-not-null-and-is-not-empty-string-in-sql-server
or
https://stackoverflow.com/questions/1106258/mysql-null-vs

server/src/main/java/org/cloudfoundry/identity/uaa/provider/JdbcIdentityProviderProvisioning.java

@@ -35,7 +35,7 @@ public class JdbcIdentityProviderProvisioning implements IdentityProviderProvisi
 
     public static final String IDENTITY_ACTIVE_PROVIDERS_QUERY = IDENTITY_PROVIDERS_QUERY + " and active=?";
 
-    public static final String IDP_WITH_ALIAS_EXISTS_QUERY = "select 1 from identity_provider idp where idp.identity_zone_id = ? and idp.alias_zid is not null and idp.alias_zid <> '' limit 1";
+    public static final String IDP_WITH_ALIAS_EXISTS_QUERY = "select 1 from identity_provider idp where idp.identity_zone_id = ? and idp.alias_zid <> '' limit 1";
 
     public static final String ID_PROVIDER_UPDATE_FIELDS = "version,lastmodified,name,type,config,active,alias_id,alias_zid".replace(",", "=?,") + "=?";
 

server/src/main/resources/org/cloudfoundry/identity/uaa/db/hsqldb/V4_109__IdP_AliasZid_IdzId_Index.sql

@@ -1 +1 @@
-CREATE INDEX IF NOT EXISTS identity_provider_alias_zid_idz_id__idx on identity_provider (alias_zid, identity_zone_id);
+CREATE INDEX IF NOT EXISTS alias_in_zone on identity_provider (identity_zone_id, alias_zid);

server/src/main/resources/org/cloudfoundry/identity/uaa/db/mysql/V4_109__IdP_AliasZid_IdzId_Index.sql

@@ -1 +1 @@
-CREATE INDEX identity_provider_alias_zid_idz_id__idx on identity_provider (alias_zid, identity_zone_id) LOCK = SHARED;
+CREATE INDEX alias_in_zone on identity_provider (identity_zone_id, alias_zid) LOCK = SHARED;

server/src/main/resources/org/cloudfoundry/identity/uaa/db/postgresql/V4_109__IdP_AliasZid_IdzId_Index.sql

@@ -1 +1 @@
-CREATE INDEX CONCURRENTLY IF NOT EXISTS identity_provider_alias_zid_idz_id__idx on identity_provider (alias_zid, identity_zone_id);
+CREATE INDEX CONCURRENTLY IF NOT EXISTS alias_in_zone on identity_provider (identity_zone_id, alias_zid) WHERE alias_zid IS NOT NULL;