Fix DS-2427 for 5.1 by consolidating problematic code into DatabaseUtils.getSchemaName() so that it can be replaced easily in future. Also cleaned up config comments

build.properties

@@ -66,14 +66,12 @@ db.password=dspace
 #db.username=dspace
 #db.password=dspace
 
-# Schema name - if your database contains multiple schemas, you can avoid problems with
-# retrieving the definitions of duplicate object names by specifying
-# the schema name here that is used for DSpace by uncommenting the following entry
-
-# NOTE: this configuration option is for PostgreSQL only. For Oracle, schema is equivalent
-# to user name. DSpace depends on the PostgreSQL understanding of schema. If you are using
-# Oracle, just leave this this value blank.
-
+# Schema name - if your database contains multiple schemas, you can avoid
+# problems with retrieving the definitions of duplicate object names by
+# specifying the schema name that is used for DSpace.
+# ORACLE USAGE NOTE: In Oracle, schema is equivalent to "username". This means
+# specifying a "db.schema" is often unnecessary (i.e. you can leave it blank),
+# UNLESS your Oracle DB Account (in db.username) has access to multiple schemas.
 db.schema = 
 
 # Maximum number of DB connections in pool

dspace-api/src/main/java/org/dspace/storage/rdbms/DatabaseManager.java

@@ -15,7 +15,6 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
-import java.sql.SQLWarning;
 import java.sql.Statement;
 import java.sql.Time;
 import java.sql.Timestamp;
@@ -35,8 +34,6 @@ import javax.sql.DataSource;
 import org.apache.commons.lang.StringUtils;
 import org.dspace.core.ConfigurationManager;
 import org.dspace.core.Context;
-import org.flywaydb.core.Flyway;
-import org.flywaydb.core.api.MigrationInfo;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -1237,10 +1234,6 @@ public class DatabaseManager
 
         try
         {
-            String schema = canonicalize(ConfigurationManager.getProperty("db.schema"));
-            if(StringUtils.isBlank(schema)){
-                schema = null;
-            }
             String catalog = null;
 
             int dotIndex = table.indexOf('.');
@@ -1254,6 +1247,9 @@ public class DatabaseManager
 
             connection = getConnection();
 
+            // Get current database schema name
+            String schema = DatabaseUtils.getSchemaName(connection);
+            
             DatabaseMetaData metadata = connection.getMetaData();
             Map<String, ColumnInfo> results = new HashMap<String, ColumnInfo>();
 

dspace-api/src/main/java/org/dspace/storage/rdbms/DatabaseUtils.java

@@ -873,8 +873,10 @@ public class DatabaseUtils
      * Get the Database Schema Name in use by this Connection, so that it can
      * be used to limit queries in other methods (e.g. tableExists()).
      * <P>
-     * For PostgreSQL, schema is simply what is configured in db.schema or "public"
-     * For Oracle, schema is actually the database *USER* or owner.
+     * NOTE: Once we upgrade to using Apache Commons DBCP / Pool version 2.0,
+     * this method WILL BE REMOVED in favor of java.sql.Connection's new
+     * "getSchema()" method.
+     * http://docs.oracle.com/javase/7/docs/api/java/sql/Connection.html#getSchema()
      * 
      * @param connection 
      *            Current Database Connection
@@ -886,27 +888,29 @@ public class DatabaseUtils
         String schema = null;
         DatabaseMetaData meta = connection.getMetaData();
         
-        // Determine our DB type
+        // Check the configured "db.schema" FIRST for the value configured there
+        schema = ConfigurationManager.getProperty("db.schema");
+        
+        // If unspecified, determine "sane" defaults based on DB type
+        if(StringUtils.isBlank(schema))
+        {
             String dbType = DatabaseManager.findDbKeyword(meta);
         
             if(dbType.equals(DatabaseManager.DBMS_POSTGRES))
             {
-            // Get the schema name from "db.schema"
-            schema = ConfigurationManager.getProperty("db.schema");
-            
-            // If unspecified, default schema is "public"
-            if(StringUtils.isBlank(schema)){
+                // For PostgreSQL, the default schema is named "public"
+                // See: http://www.postgresql.org/docs/9.0/static/ddl-schemas.html
                 schema = "public";
             }
-        }
             else if (dbType.equals(DatabaseManager.DBMS_ORACLE))
             {
-            // Schema is actually the user account
+                // For Oracle, default schema is actually the user account
                 // See: http://stackoverflow.com/a/13341390
                 schema = meta.getUserName();
             }
             else
                 schema = null;
+        }
         
         return schema;
     }

dspace/config/dspace.cfg

@@ -63,9 +63,9 @@ db.password = ${db.password}
 # Schema name - if your database contains multiple schemas, you can avoid
 # problems with retrieving the definitions of duplicate object names by
 # specifying the schema name that is used for DSpace.
-# NOTE: this configuration option is for PostgreSQL only. For Oracle, schema
-# is equivalent to user name. DSpace depends on the PostgreSQL understanding
-# of schema. If you are using Oracle, just leave this this value blank.
+# ORACLE USAGE NOTE: In Oracle, schema is equivalent to "username". This means
+# specifying a "db.schema" is often unnecessary (i.e. you can leave it blank),
+# UNLESS your Oracle DB Account (in db.username) has access to multiple schemas.
 db.schema = ${db.schema}
 
 ## Connection pool parameters