Fix division by zero

janmotl · Apr 17, 2018 · 6c4eb34 · 6c4eb34
1 parent 2a8ad6f
commit 6c4eb34
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Showing 3 changed files with 15 additions and 15 deletions.
diff --git a/src/vendor/MSSQL.java b/src/vendor/MSSQL.java
@@ -139,7 +139,7 @@ public void getColumnStatistics(String databaseName, String schemaName, List<Tab
 				"\t) nullCounter\n" +
 				"\n" +
 				" \tDELETE FROM #Density\n" +
-				" \tdelete FROM #Histogram\n" +
+				" \tDELETE FROM #Histogram\n" +
 				"-- End\n" +
 				"FETCH NEXT FROM MY_CURSOR INTO @TABLE_NAME, @STAT_NAME\n" +
 				"END\n" +
@@ -182,8 +182,8 @@ public void getColumnStatistics(String databaseName, String schemaName, List<Tab
 				}
 				column.setTextMin(rs.getString(3));
 				column.setTextMax(rs.getString(4));
-				column.setNullRatio(column.getRowCount()==null ? null : rs.getDouble(5) / column.getRowCount());
-				column.setUniqueRatio(column.getRowCount()==null ? null : (1/rs.getDouble(6)) / column.getRowCount());
+				column.setNullRatio((column.getRowCount()==null || column.getRowCount()==0) ? null : rs.getDouble(5) / column.getRowCount());
+				column.setUniqueRatio(column.getRowCount()==null || column.getRowCount()==0 ? null : (1/rs.getDouble(6)) / column.getRowCount());
 				column.setWidthAvg(rs.getDouble(7));
 			}
 		}

diff --git a/src/vendor/Oracle.java b/src/vendor/Oracle.java
@@ -193,10 +193,10 @@ public void getColumnStatistics(String databaseName, String schemaName, List<Tab
 				if (table == null) continue; // The table is blacklisted -> skip it
 				@Nullable Column column = table.getColumn(rs.getString(2)); // Oracle supports "hidden" columns that are by default not listed in getColumns() JDBC call but statistics is still calculated on them
 				if (column == null) continue;
-				column.setUniqueRatio(column.getRowCount()==null ? null : rs.getDouble(3) / column.getRowCount()); // If we have no knowledge about the column, return null
+				column.setUniqueRatio(column.getRowCount()==null || column.getRowCount()==0 ? null : rs.getDouble(3) / column.getRowCount()); // If we have no knowledge about the column, return null
 				column.setTextMin(rs.getString(4));
 				column.setTextMax(rs.getString(5));
-				column.setNullRatio(column.getRowCount()==null ? null : rs.getDouble(6) / column.getRowCount());
+				column.setNullRatio(column.getRowCount()==null || column.getRowCount()==0 ? null : rs.getDouble(6) / column.getRowCount());
 				column.setWidthAvg(rs.getDouble(7));
 			}
 		}

diff --git a/src/vendor/QualityControl.java b/src/vendor/QualityControl.java
@@ -14,20 +14,20 @@ public static void qcNumericalValues(List<Table> tables) {
         for (Table table : tables) {
             for (Column column : table.getColumnList()) {
                 // Doubles
-                if (column.getNullRatio() != null && column.getNullRatio().isInfinite()) LOGGER.severe("NullRatio is infinite");
-                if (column.getUniqueRatio() != null && column.getUniqueRatio().isInfinite()) LOGGER.severe("UniqueRatio is infinite");
-                if (column.getWidthAvg() != null && column.getWidthAvg().isInfinite()) LOGGER.severe("WidthAvg is infinite");
+                if (column.getNullRatio() != null && column.getNullRatio().isInfinite()) LOGGER.severe("NullRatio in " + table.getName() + "." + column.getName() + " is infinite");
+                if (column.getUniqueRatio() != null && column.getUniqueRatio().isInfinite()) LOGGER.severe("UniqueRatio " + table.getName() + "." + column.getName() + " is infinite");
+                if (column.getWidthAvg() != null && column.getWidthAvg().isInfinite()) LOGGER.severe("WidthAvg " + table.getName() + "." + column.getName() + " is infinite");
 
-                if (column.getNullRatio() != null && column.getNullRatio().isNaN()) LOGGER.severe("NullRatio is NaN");
-                if (column.getUniqueRatio() != null && column.getUniqueRatio().isNaN()) LOGGER.severe("UniqueRatio is NaN");
-                if (column.getWidthAvg() != null && column.getWidthAvg().isNaN()) LOGGER.severe("WidthAvg is NaN");
+                if (column.getNullRatio() != null && column.getNullRatio().isNaN()) LOGGER.severe("NullRatio " + table.getName() + "." + column.getName() + " is NaN");
+                if (column.getUniqueRatio() != null && column.getUniqueRatio().isNaN()) LOGGER.severe("UniqueRatio " + table.getName() + "." + column.getName() + " is NaN");
+                if (column.getWidthAvg() != null && column.getWidthAvg().isNaN()) LOGGER.severe("WidthAvg " + table.getName() + "." + column.getName() + " is NaN");
 
-                if (column.getNullRatio() != null && column.getNullRatio() < 0) LOGGER.severe("NullRatio is negative");
-                if (column.getUniqueRatio() != null && column.getUniqueRatio() < 0) LOGGER.severe("UniqueRatio is negative");
-                if (column.getWidthAvg() != null && column.getWidthAvg() < 0) LOGGER.severe("WidthAvg is negative");
+                if (column.getNullRatio() != null && column.getNullRatio() < 0) LOGGER.severe("NullRatio " + table.getName() + "." + column.getName() + " is negative");
+                if (column.getUniqueRatio() != null && column.getUniqueRatio() < 0) LOGGER.severe("UniqueRatio " + table.getName() + "." + column.getName() + " is negative");
+                if (column.getWidthAvg() != null && column.getWidthAvg() < 0) LOGGER.severe("WidthAvg " + table.getName() + "." + column.getName() + " is negative");
 
                 // Integers
-                if (column.getRowCount() != null && column.getRowCount() < 0) LOGGER.severe("RowCount is negative");
+                if (column.getRowCount() != null && column.getRowCount() < 0) LOGGER.severe("RowCount " + table.getName() + "." + column.getName() + " is negative");
             }
         }
 	}