simplify padding with formula

prestodb · Jan 13, 2025 · c640cde · c640cde
1 parent 51b1f96
commit c640cde
Showing 1 changed file with 9 additions and 13 deletions.
diff --git a/presto-clickhouse/src/main/java/com/facebook/presto/plugin/clickhouse/TimestampUtil.java b/presto-clickhouse/src/main/java/com/facebook/presto/plugin/clickhouse/TimestampUtil.java
@@ -19,21 +19,17 @@ private TimestampUtil() {}
 
     public static int getMillisecondsFromTimestampString(String timestampString)
     {
-        int milliseconds = 0;
         int dotIndex = timestampString.indexOf('.');
+        if (dotIndex == -1) {
+            return 0;
+        }
 
-        if (dotIndex != -1) {
-            String fractionalPart = timestampString.substring(dotIndex + 1);
-            int fractionalLength = fractionalPart.length();
-            // Normalize the fractional part to at least 3 digits by padding with zeros. e.g., 7 -> 700; 70 -> 700
-            if (fractionalLength == 1) {
-                fractionalPart += "00";
-            }
-            else if (fractionalLength == 2) {
-                fractionalPart += "0";
-            }
-            milliseconds = Integer.parseInt(fractionalPart);
+        String fraction = timestampString.substring(dotIndex + 1);
+        int nonNormalized = Integer.parseInt(fraction);
+        if (nonNormalized == 0 || fraction.length() == 3) {
+            return nonNormalized;
         }
-        return milliseconds;
+        // this will make sure it's always 3 digits. e.g., 7 -> 700; 71 -> 710; 7591 -> 759
+        return (int) Math.round(nonNormalized * Math.pow(10, -(Math.floor(Math.log10(nonNormalized)) - 2)));
     }
 }