jodd-db/src/main/java/jodd/db/oom/sqlgen/chunks/SqlChunk.java
protected boolean isEmptyColumnValue(final DbEntityColumnDescriptor dec, final Object value) {
		if (value == null) {
			return true;
		}

		// special case for ID column
		if (dec.isId() && value instanceof Number) {
			final double d = ((Number) value).doubleValue();
			if (d == 0.0d) {
				return true;
			}
		}

		// special case for primitives
		if (dec.getPropertyType().isPrimitive()) {
			if (char.class == dec.getPropertyType()) {
				final Character c = ((Character) value);
				if ('\u0000' == c.charValue()) {
					return true;
				}
			} else {
				final double d = ((Number) value).doubleValue();
				if (d == 0) {
					return true;
				}
			}
		}

		// special case for strings
		if (value instanceof CharSequence) {
			if (StringUtil.isBlank((CharSequence) value)) {
				return true;
			}
		}

		return false;
	}
protected boolean isEmptyColumnValue(final DbEntityColumnDescriptor dec, final Object value) {
		if (value == null) {
			return true;
		}

		// special case for ID column
		if (dec.isId() && value instanceof Number) {
			final double d = ((Number) value).doubleValue();
			if (d == 0.0d) {
				return true;
			}
		}

		// special case for primitives
		if (dec.getPropertyType().isPrimitive()) {
			if (char.class == dec.getPropertyType()) {
				final Character c = ((Character) value);
				if ('\u0000' == c.charValue()) {
					return true;
				}
			} else {
				final double d = ((Number) value).doubleValue();
				if (d == 0) {
					return true;
				}
			}
		}

		// special case for strings
		if (value instanceof CharSequence) {
			if (StringUtil.isBlank((CharSequence) value)) {
				return true;
			}
		}

		return false;
	}
Returns <code>true</code> if a value is considered empty i.e. not existing.