Comments

Comments

This document describes the comment syntax supported by MatrixOne.

MatrixOne supports three comment styles:

Use # character to comment a line.

1. mysql> select 100-99;   # This comment continues to the end of line
2. +----------+
3. | 100 - 99 |
4. +----------+
5. |        1 |
6. +----------+
7. 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).

1. mysql> select 100-99;   -- This comment continues to the end of line
2. +----------+
3. | 100 - 99 |
4. +----------+
5. |        1 |
6. +----------+
7. 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.

1. mysql> select 100 /* this is an in-line comment */ -99;
2. +----------+
3. | 100 - 99 |
4. +----------+
5. |        1 |
6. +----------+
7. 1 row in set (0.01 sec)

Or:

1. mysql> select 100
2. /*
3. this is an in-line comment
4. */
5. -99;
6. +----------+
7. | 100 - 99 |
8. +----------+
9. |        1 |
10. +----------+
11. 1 row in set (0.01 sec)

MySQL-compatible comment syntax

The same as MySQL, MatrixOne supports a variant of C comment style:

1. mysql> select 100 /*! Specific code */ -99;
2. +----------+
3. | 100 - 99 |
4. +----------+
5. |        1 |
6. +----------+
7. 1 row in set (0.02 sec)

Or:

1. mysql> select 100 /*!50110 Specific code */ -99;
2. +----------+
3. | 100 - 99 |
4. +----------+
5. |        1 |
6. +----------+
7. 1 row in set (0.02 sec)

MatrixOne specific comment syntax

MatrixOne supports a variant of C comment style:

1. mysql> select 100-99;   // This comment continues to the end of line
2. +----------+
3. | 100 - 99 |
4. +----------+
5. |        1 |
6. +----------+
7. 1 row in set (0.03 sec)

Or:

1. mysql> // This comment continues to the line
2. -> select 100-99;
3. +----------+
4. | 100 - 99 |
5. +----------+
6. |        1 |
7. +----------+

Constraints

MatrixOne does not support nested comments.