From 386c9830981af74fdd69e75536657c8fca46a148 Mon Sep 17 00:00:00 2001
From: hunshenshi <289517357@qq.com>
Date: Sat, 7 Dec 2024 18:26:10 +0800
Subject: [PATCH] [common] Fix FLOAT precision checking. (#4656)

---
 .../main/java/org/apache/paimon/utils/TypeUtils.java   | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/paimon-common/src/main/java/org/apache/paimon/utils/TypeUtils.java b/paimon-common/src/main/java/org/apache/paimon/utils/TypeUtils.java
index 8d8d84953da7..50096ab63621 100644
--- a/paimon-common/src/main/java/org/apache/paimon/utils/TypeUtils.java
+++ b/paimon-common/src/main/java/org/apache/paimon/utils/TypeUtils.java
@@ -144,11 +144,13 @@ public static Object castFromStringInternal(String s, DataType type, boolean isC
                 } else {
                     // Compatible canal-cdc
                     Float f = Float.valueOf(s);
-                    if (f.toString().length() != s.length()) {
-                        throw new NumberFormatException(
-                                s + " cannot be cast to float due to precision loss");
-                    } else {
+                    // Validate precision by comparing the rounded value
+                    if ((double) f == d || Math.abs(f - d) < Math.abs(d * 1e-6)) {
                         return f;
+                    } else {
+                        // Significant precision loss detected
+                        throw new NumberFormatException(
+                                s + " cannot be cast to FLOAT due to precision loss");
                     }
                 }
             case DOUBLE: