There are three ways to view the SQL table structure: 1. Use the DESCRIBE or DESC command (suitable for MySQL and MariaDB), and directly enter DESCRIBE table_name; or DESC table_name; to quickly obtain information such as field name, type, primary key, whether NULL is allowed; 2. Query INFORMATION_SCHEMA.COLUMNS (suitable for most SQL databases), by executing SELECT COLUMN_NAME, DATA_TYPE, IS_NULLABLE, COLUMN_DEFAULT FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'your_table_name'; Get more detailed and highly compatible table structure data; 3. Use graphical tools such as phpMyAdmin, DBeaver, and Navicat to intuitively view and export table structure through interface operations. In addition, different databases also provide other shortcut commands such as PostgreSQL's \d table_name and SQL Server's sp_columns stored procedures, which can select appropriate methods according to the usage scenario.

To view the table structure in SQL (that is, the schema of the table), the most direct way is to use the commands provided by the database or query the system table/information schema. Different database systems may have slightly different syntax, but the core idea is the same: find information such as field name, type, and whether to allow empty.

Use DESCRIBE or DESC (for MySQL, MariaDB)

If you are using MySQL or MariaDB, the easiest way is to use DESCRIBE or its abbreviation DESC :

 DESCRIBE table_name;
-- or DESC table_name;

This lists the names, data types, whether they are primary keys, whether they are allowed to be NULL, etc. of all columns in the table. Suitable for quick viewing, but limited functions, so you cannot do too complex queries.

Query INFORMATION_SCHEMA.COLUMNS (for most SQL databases)

If you need more detailed information, or are using PostgreSQL, SQL Server, etc. that do not support DESCRIBE , it is recommended to query INFORMATION_SCHEMA.COLUMNS :

 SELECT COLUMN_NAME, DATA_TYPE, IS_NULLABLE, COLUMN_DEFAULT
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'your_table_name';

The advantage of this method is that it has good compatibility and is supported by almost all SQL databases. You can add more fields as needed, such as CHARACTER_MAXIMUM_LENGTH (field length) or COLUMN_KEY (whether it is a primary key) etc.

Use database management tools (such as phpMyAdmin, DBeaver, Navicat)

If you are not used to writing SQL statements, you can also use graphical tools to view the table structure:

• phpMyAdmin: Click the table name and select the "Structure" tab
• DBeaver/Navicat: Expand the table in the left object browser, right-click to view the structure or double-click to open it

These tools usually display field names, types, default values, comments and other information in tabular form, which is very intuitive and convenient for exporting structures.

Other tips

• You can use the \d table_name command in PostgreSQL (on the psql command line)

• You can use sp_columns stored procedure in SQL Server:

   EXEC sp_columns @table_name = 'your_table_name';

  These methods have their own advantages in different scenarios, such as DESCRIBE or \d is faster when operating the command line, and INFORMATION_SCHEMA is more suitable when writing scripts or cross-platform compatibility.

  Basically these are the methods. Although there seem to be several options, just choose one that suits your current database and usage habits.

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