Issue #32. Remove empty tables from analysis. This feature is managed…

… by "skip-empty-tables" attribute in db.properties property file.
armenak · Aug 25, 2015 · dbf4dd1 · dbf4dd1
1 parent 081928c
commit dbf4dd1
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Showing 2 changed files with 35 additions and 7 deletions.
diff --git a/DataAnonymizer/src/main/java/com/strider/dataanonymizer/DataDiscoverer.java b/DataAnonymizer/src/main/java/com/strider/dataanonymizer/DataDiscoverer.java
@@ -59,9 +59,6 @@
 public class DataDiscoverer extends Discoverer {
 
     private static Logger log = getLogger(DataDiscoverer.class);
-//    TODO: Uncomment back in if/when we need it
-//    private static List firstAndLastNames = new ArrayList();
-
 
     @Override
     public List<MatchMetaData> discover(IDBFactory factory, Properties dataDiscoveryProperties, Set<String> tables) 

diff --git a/DataAnonymizer/src/main/java/com/strider/dataanonymizer/database/metadata/MetaData.java b/DataAnonymizer/src/main/java/com/strider/dataanonymizer/database/metadata/MetaData.java
@@ -17,19 +17,23 @@
  */
 package com.strider.dataanonymizer.database.metadata;
 
-import static org.apache.log4j.Logger.getLogger;
-
+import com.strider.dataanonymizer.utils.SQLToJavaMapping;
 import java.sql.Connection;
 import java.sql.DatabaseMetaData;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.sql.Statement;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Properties;
-
 import org.apache.log4j.Logger;
+import static org.apache.log4j.Logger.getLogger;
+import static org.apache.log4j.Logger.getLogger;
+import static org.apache.log4j.Logger.getLogger;
+import static org.apache.log4j.Logger.getLogger;
 
-import com.strider.dataanonymizer.utils.SQLToJavaMapping;
 
 /**
  * Class to hold common logic between different metadata implementations.
@@ -62,12 +66,15 @@ public List<MatchMetaData> getMetaData(String columnType) {
     protected ResultSet getTableRS(DatabaseMetaData md) throws SQLException {
         return md.getTables(null, schema, null, new String[] {"TABLE"});
     }
+
     protected ResultSet getPKRS(DatabaseMetaData md, String tableName) throws SQLException {
         return md.getPrimaryKeys(null, schema, tableName);
     }
+
     protected ResultSet getColumnRS(DatabaseMetaData md, String tableName) throws SQLException {
         return md.getColumns(null, schema, tableName, null);
     }
+
     protected String getColumnName(ResultSet columnRS) throws SQLException {
         return columnRS.getString(4);
     }
@@ -82,11 +89,20 @@ public List<MatchMetaData> getMetaData() {
             DatabaseMetaData md = connection.getMetaData();
 
             String schemaName = databaseProperties.getProperty("schema");
+            String skipEmptyTables = databaseProperties.getProperty("skip-empty-tables");
+
             log.info("Fetching table names from schema " + schemaName);
             try (ResultSet tableRS = getTableRS(md)) {
                 while (tableRS.next()) {
                     String tableName = tableRS.getString(3);
+
+                    // Skip table if it is empty
+                    if ( (skipEmptyTables != null && skipEmptyTables.equals("true")) && (getRowNumber(tableName) == 0) ) {
+                        log.info("Skipping empty table " + tableName);
+                        continue;
+                    }
                     log.info("Processing table " + tableName);
+
                     List<String> pkeys = new ArrayList<>();
                     try (ResultSet pkRS = getPKRS(md, tableName)) {
                         while (pkRS.next()) {
@@ -120,4 +136,19 @@ String getColumnType(ResultSet columnRS) throws SQLException {
         }
         return colType;
     }
+
+    private int getRowNumber(String table) {
+        int rowNum = 0;
+
+        try (Statement stmt = connection.createStatement();) {
+            try (ResultSet rs = stmt.executeQuery("SELECT count(*) FROM " + table);) {
+                rs.next();
+                rowNum = rs.getInt(1);
+            }
+        } catch (SQLException sqle) {
+            log.error(sqle.toString());
+        }
+
+        return rowNum;
+    }
 }