Making Long Output Lines More Readable

1.28.1 Problem

The output lines from a query are too long. They wrap around and make a mess of your screen.

1.28.2 Solution

Use vertical output format.

1.28.3 Discussion

Some queries generate output lines that are so long they take up more than one line on your terminal, which can make query results difficult to read. Here is an example that shows what excessively long query output lines might look like on your screen:[9]

[9] Prior to MySQL 3.23.32, omit the FULL keyword from the SHOW COLUMNS statement.

mysql> SHOW FULL COLUMNS FROM limbs;
+-------+-------------+------+-----+---------+-------+-------------------------
--------+
| Field | Type | Null | Key | Default | Extra | Privileges
 |
+-------+-------------+------+-----+---------+-------+-------------------------
--------+
| thing | varchar(20) | YES | | NULL | | select,insert,update,ref
erences |
| legs | int(11) | YES | | NULL | | select,insert,update,ref
erences |
| arms | int(11) | YES | | NULL | | select,insert,update,ref
erences |
+-------+-------------+------+-----+---------+-------+-------------------------
--------+

An alternative is to generate "vertical" output with each column value on a separate line. This is done by terminating a query with G rather than with a ; character or with g. Here's what the result from the preceding query looks like when displayed using vertical format:

mysql> SHOW FULL COLUMNS FROM limbsG
*************************** 1. row ***************************
 Field: thing
 Type: varchar(20)
 Null: YES
 Key:
 Default: NULL
 Extra:
Privileges: select,insert,update,references
*************************** 2. row ***************************
 Field: legs
 Type: int(11)
 Null: YES
 Key:
 Default: NULL
 Extra:
Privileges: select,insert,update,references
*************************** 3. row ***************************
 Field: arms
 Type: int(11)
 Null: YES
 Key:
 Default: NULL
 Extra:
Privileges: select,insert,update,references

To specify vertical output from the command line, use the -E (or --vertical) option when you invoke mysql. This affects all queries issued during the session, something that can be useful when using mysql to execute a script. (If you write the statements in the SQL script file using the usual semicolon terminator, you can select normal or vertical output from the command line by selective use of -E.)

Using the mysql Client Program

Writing MySQL-Based Programs

Record Selection Techniques

Working with Strings

Working with Dates and Times

Sorting Query Results

Generating Summaries

Modifying Tables with ALTER TABLE

Obtaining and Using Metadata

Importing and Exporting Data

Generating and Using Sequences

Using Multiple Tables

Statistical Techniques

Handling Duplicates

Performing Transactions

Introduction to MySQL on the Web

Incorporating Query Resultsinto Web Pages

Processing Web Input with MySQL

Using MySQL-Based Web Session Management

Appendix A. Obtaining MySQL Software

Appendix B. JSP and Tomcat Primer

Appendix C. References



MySQL Cookbook
MySQL Cookbook
ISBN: 059652708X
EAN: 2147483647
Year: 2005
Pages: 412
Authors: Paul DuBois

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