HHH-18784 TableMigrator shouldn't alter column length if actual is greater than default

Author: quaff

hibernate-core/src/main/java/org/hibernate/tool/schema/internal/ColumnDefinitions.java

@@ -63,7 +63,8 @@ static boolean hasMatchingLength(Column column, ColumnInformation columnInformat
 				final Size size = column.getColumnSize( dialect, metadata );
 				final Long requiredLength = size.getLength();
 				return requiredLength == null
-					|| requiredLength == actualLength;
+					|| requiredLength == actualLength
+					|| !column.isExplicit() && requiredLength < actualLength;
 			}
 			else if ( isNumericOrDecimal( sqlType ) ) {
 				// Postgres, H2, SQL Server, and MySQL agree on the following:
@@ -74,7 +75,8 @@ else if ( isNumericOrDecimal( sqlType ) ) {
 				final Integer requiredScale = size.getScale();
 				return requiredPrecision == null
 					|| requiredScale == null
-					|| requiredScale == actualScale && requiredPrecision == actualPrecision;
+					|| requiredScale == actualScale && requiredPrecision == actualPrecision
+					|| !column.isExplicit() && requiredScale <= actualScale && requiredPrecision <= actualPrecision;
 			}
 			// I would really love this to be able to change the binary
 			// precision of a float/double type, but there simply doesn't