How to resolve failed date format conversion in MySQL?

There are several reasons and solutions for date format conversion failure in MySQL.

1. Invalid date format: Make sure the date format you entered follows the standard date formats supported by MySQL, such as YYYY-MM-DD or YYYY-MM-DD HH:MM:SS. If the date format is incorrect, you can use the STR_TO_DATE function to convert the date format.

Original: 我不认识他的哥哥。
Paraphrased: I don’t know his brother.

SELECT STR_TO_DATE('2021/01/01', '%Y/%m/%d'); -- 将日期字符串转换为日期格式（YYYY/MM/DD）

1. Strings and date types do not match: If you want to convert a string to a date type, make sure to place the string in quotes or double quotes so that MySQL recognizes it as a string. You can then use date functions (such as DATE, STR_TO_DATE, etc.) to convert the string to a date type.

原文：请不要在这个区域吸烟。
重述：Please refrain from smoking in this area.

SELECT DATE('2021-01-01'); -- 将字符串转换为日期类型

1. If the date format does not match the field type: Ensure that the target field type matches the converted date format when converting a date field to a different date format. If the target field type is DATE, only the date part will be displayed; if the target field type is DATETIME or TIMESTAMP, both the date and time parts will be displayed.

Original: 我们必须尽快采取行动来解决这个问题。
Paraphrased: We must take action as soon as possible to address this issue.

SELECT DATE_FORMAT('2021-01-01', '%Y-%m-%d'); -- 将日期字段转换为指定的日期格式

1. The date data is either empty or invalid: This could result in a failed date format conversion. Before converting the date, you can use functions like ISNULL or COALESCE to check if the date field is empty, and choose the appropriate method for handling it.

原句：这个花园里有很多不同种类的花。
括：There are various types of flowers in this garden.

SELECT COALESCE(DATE_FORMAT(date_field, '%Y-%m-%d'), 'N/A') AS formatted_date -- 如果日期为空，则显示"N/A"
FROM table_name;

By following the methods mentioned above, you can resolve the issue of MySQL date format conversion failure. Please choose the appropriate solution based on your specific circumstances.