Comments

This document describes the comment syntax supported by MatrixOne.

MatrixOne supports three comment styles:

• Use # character to comment a line.

  mysql> select 100-99;   # This comment continues to the end of line
  +----------+
  | 100 - 99 |
  +----------+
  |        1 |
  +----------+
  1 row in set (0.01 sec)
  

• Use -- to comment a line. The -- (double-dash) comment style requires the second dash to be followed by at least one whitespace or control character (such as a space, tab, newline, and so on).

  mysql> select 100-99;   -- This comment continues to the end of line
  +----------+
  | 100 - 99 |
  +----------+
  |        1 |
  +----------+
  1 row in set (0.01 sec)
  

• From a /* sequence to the following */ sequence, as in the C programming language. This syntax enables a comment to extend over multiple lines because the beginning and closing sequences need not be on the same line.

  mysql> select 100 /* this is an in-line comment */ -99;
  +----------+
  | 100 - 99 |
  +----------+
  |        1 |
  +----------+
  1 row in set (0.01 sec)
  

  Or:

  mysql> select 100
  /*
  this is an in-line comment
  */
  -99;
  +----------+
  | 100 - 99 |
  +----------+
  |        1 |
  +----------+
  1 row in set (0.01 sec)
  

MatrixOne specific comment syntax

• MatrixOne supports C comment style as below:

mysql> select 100-99;   // This comment continues to the end of line
+----------+
| 100 - 99 |
+----------+
|        1 |
+----------+
1 row in set (0.03 sec)

Or:

mysql> // This comment continues to the line
    -> select 100-99;
+----------+
| 100 - 99 |
+----------+
|        1 |
+----------+

• MatrixOne dose not support C comment style as below:

mysql> select 100 /*! Specific code */ -99;
ERROR 1064 (HY000): SQL parser error: You have an error in your SQL syntax; check the manual that corresponds to your MatrixOne server version for the right syntax to use. syntax error at line 1 column 28 near " code */ -99";

Or:

mysql> select 100 /*!50110 Specific code */ -99;
ERROR 1064 (HY000): SQL parser error: You have an error in your SQL syntax; check the manual that corresponds to your MatrixOne server version for the right syntax to use. syntax error at line 1 column 33 near " code */ -99";

Constraints

MatrixOne does not support nested comments.