What are the rules for writing SQL statements?

The rules for writing SQL statements are as follows:

1. In SQL, case sensitivity is not a concern, but it is commonly agreed upon to use uppercase for keywords and lowercase for table and column names to enhance code readability.
2. It is possible to write SQL statements in one line or spread out over multiple lines, but for better readability, it is generally recommended to have each keyword or logical section on a separate line.
3. SQL statements are terminated by a semicolon to indicate the end of the statement.
4. SQL statements can utilize comments, with single-line comments starting with “–” and multi-line comments starting with “/” and ending with “/”.
5. In SQL statements, strings should be enclosed in either single or double quotes, while types like numbers and dates do not need to be enclosed.
6. In SQL statements, you can use spaces, indentation, line breaks, and other formatting symbols to improve the readability of the code.
7. Identifiers such as keywords, table names, and column names in SQL statements should adhere to the naming conventions of the database. It is generally recommended to use English characters and underscores, and avoid using special characters or Chinese characters.
8. Conditions in SQL statements should be enclosed in parentheses to clarify the logical order.
9. Functions, operators, keywords and other elements in SQL statements must be used according to the syntax rules, ensuring that data types match.