Why can't mysql only write one row when creating a table?

The reasons why MySQL can only write one row when creating a table include: 1. max_allowed_packet variable limitation; 2. Safe mode; 3. JDBC driver limitation; 4. ORM framework limitation; 5. innodb_log_file_size variable limitation. You can resolve this issue by increasing the value of the max_allowed_packet variable, disabling safe mode, using a newer JDBC driver, using simpler query syntax, or increasing the value of the innodb_log_file_size variable.

The reason why MySQL can only write one row when creating a table

In MySQL, the syntax for creating a table is usually as follows:

<code>CREATE TABLE table_name (
    column1 data_type,
    column2 data_type,
    ...
    columnn data_type
);</code>

If the create table statement can only write one row, there may be the following reasons:

MySQL command line configuration

• max_allowed_packet Variable : This variable limits the maximum number of bytes that MySQL can handle for a single query. If a query exceeds this limit, MySQL will refuse to execute it.
• Safety Mode: MySQL's safe mode limits the length of queries to prevent malicious queries.

Application Limitations

• JDBC Driver: Some JDBC drivers limit the length of query statements.
• ORM Framework: Object-relational mapping (ORM) frameworks may use custom syntax or automatically generate queries, which may have length limitations.

Database settings

• innodb_log_file_size variable : This variable limits the size of a single InnoDB redo log file. If a CREATE TABLE statement would generate a redo log that exceeds this limit, MySQL will refuse to execute it.

Solution

To solve this problem, you can try the following methods:

• Increase the value of the max_allowed_packet variable : Increase this value by modifying the MySQL configuration file and restarting the MySQL service.
• Disable safe mode: Disable the safe mode option in the MySQL configuration file.
• Use newer JDBC drivers: Upgrade to newer versions of drivers that generally support longer queries.
• Use simpler query syntax: Avoid using nested queries or complex join table queries, which may generate longer statements.
• Increase the value of the innodb_log_file_size variable: Increase the value by modifying the MySQL configuration file and restarting the MySQL service.

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