postgresql源代码为：

public void sendInteger2(int val) throws IOException {
if (val >= -32768 && val <= 32767) {
this.int2Buf[0] = (byte)(val >>> 8);
this.int2Buf[1] = (byte)val;
this.pgOutput.write(this.int2Buf);
} else {
throw new IOException("Tried to send an out-of-range integer as a 2-byte value: " + val);
}
}

因此我个人认为是有限制的 ，32767