Field 'field_name' doesn't have a default value - How to solve MySQL error: Field has no default value

Title: Field 'field_name' doesn't have a default value - How to solve MySQL error: The field has no default value, specific code examples are needed

Introduction:
MySQL is a commonly used relational database management system widely used in web development and data storage fields. When using MySQL, you sometimes encounter the error message: "Field 'field_name' doesn't have a default value". This article will introduce the cause of this error and provide solutions and specific code examples to help readers solve this common problem.

1. Analysis of error reasons:
Fields in MySQL can be set to required (NOT NULL), but if an initial value is not explicitly provided for the field when inserting data, MySQL will report an error: "Field 'field_name' doesn't have a default value". This error is usually caused by the following two situations:

1. When inserting data, the specific value of the field that does not have a default value is not provided.
2. When defining the table structure, an initial value is not explicitly set for fields that do not have a default value.

2. Solution:
For the above two situations, we provide solutions as follows:

2.1 When inserting data, provide specific values ​​for fields that do not have default values. :
The way to solve this problem is to provide specific values ​​for fields that do not have default values ​​when inserting data. The following is a sample code:

INSERT INTO table_name (field1, field2, field3) VALUES ('value1', 'value2', 'value3');

In the above code, we provide specific values ​​for the fields field1, field2, and field3 that do not have default values, thus avoiding errors.

2.2 When defining the table structure, set an initial value for the field that does not have a default value:
The way to solve this problem is to set an initial value for the field that does not have a default value when defining the table structure. The following is a sample code:

CREATE TABLE table_name (
    field1 INT NOT NULL DEFAULT 0,
    field2 VARCHAR(255) NOT NULL DEFAULT '',
    field3 DATE NOT NULL DEFAULT '1900-01-01'
);

In the above code, we set default values ​​for the three fields field1, field2, and field3 in the table, which are 0, empty string, and the specified date respectively. This way, when data is inserted and no specific values ​​are provided for these fields, MySQL will use default values ​​to populate these fields.

3. Summary:
When using MySQL, when encountering an error: "Field 'field_name' doesn't have a default value", we can provide specific values ​​for fields that do not have a default value. Or set default values ​​for these fields in the table structure to solve this problem. Through the demonstration of specific code examples, I believe readers can better understand and apply these solutions and avoid encountering this error in actual development.

What is certain is that mastering MySQL error resolution skills can greatly improve our work efficiency and code quality. I hope that the content of this article will be helpful to readers, so that everyone can better deal with and solve problems in MySQL. Happy programming everyone!

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