Laravel 5.4.36日期类型输入语法无效报错，求错误原因分析

云原生阿岚

2026-5-19

Understanding the "invalid input syntax for type date: """ Error in Laravel 5.4.36

Hey there! Let's break down exactly why you're running into this error and how to fix it.

What's causing the error?

The root problem here is that your date_out column is a date-type field in your database, and you're trying to compare it to an empty string (''). Databases (especially PostgreSQL, which this error message is common with) can't convert an empty string into a valid date value—there's no logical date equivalent to an empty string. When it hits this invalid comparison, it throws the invalid input syntax for type date error because it can't process the empty string as a date.

How to fix this in your Laravel query

Depending on what you're actually trying to accomplish, here are the correct approaches:

If you want to find records where date_out hasn't been set (is null): Instead of comparing to an empty string, use Laravel's whereNull method. Your query should look like this:
```
$results = DB::table('your_table as b')
            ->whereNull('b.date_out')
            ->get();
```

If you're using a dynamic value (like user input) that might be empty: Add a check to only include the where clause when the value is a valid date. For example:

$filterDate = request()->input('date_filter'); // Replace with your variable source

$query = DB::table('your_table as b');

if (!empty($filterDate) && strtotime($filterDate)) {
    $query->where('b.date_out', '<', $filterDate);
}

$results = $query->get();

If you meant to compare to a specific date but accidentally passed an empty string: Double-check where that empty string is coming from—maybe a form input wasn't filled out, or a variable wasn't properly initialized. Make sure you're passing a valid date string (like '2024-05-20') that matches your database's expected date format.