[
    {
        "role": "user",
        "content": "what%20is%20comment%20character%20for%20sql%3F"
    },
    {
        "role": "assistant",
        "content": "In standard SQL, there are two main ways to write comments (i.e. text ignored by the engine) in your SQL code:\n\n---\n\n**1. Single-line comment**  \n- Starts with two hyphens `--`  \n- Everything from `--` to the end of that line is treated as a comment ([sqlite.org](https://sqlite.org/lang_comment.html?utm_source=openai))  \n- Example:  \n  ```sql\n  SELECT * FROM Users;  -- This is a single-line comment\n  ```\n\n**2. Block or multi-line comment**  \n- Starts with `/*` and ends with `*/`  \n- Can span multiple lines ([w3schools.com](https://www.w3schools.com/sql/sql_comments.asp?utm_source=openai))  \n- Example:  \n  ```sql\n  /* This is a\n     multi-line comment\n     over several lines */\n  SELECT * FROM Orders;\n  ```\n\n---\n\n### Variations / Database-specific rules\n\n- Some SQL dialects support a `#` prefix for single-line comments (e.g. Google Cloud Dataflow SQL) ([cloud.google.com](https://cloud.google.com/dataflow/docs/reference/sql/lexical?utm_source=openai))  \n- Oracle SQL also allows using `REM` or `@` at the start of a line to denote a comment in certain tools (like SQL*Plus) ([querytool.com](https://www.querytool.com/help/1135.htm?utm_source=openai))  \n- Be aware: not all SQL environments support all styles (especially `#` or `REM`) ([docs.exasol.com](https://docs.exasol.com/db/latest/microcontent/Resources/MicroContent/general/comments-in-sql.htm?utm_source=openai))  \n\n---\n\nIf you tell me which database system you're using (MySQL, PostgreSQL, SQL Server, Oracle, etc.), I can confirm exactly which comment styles are supported in *your* environment."
    }
]