MYSQLQUERY

Name

mysqlquery

Purpose

Submit MySQL query and get response as vectors of data (like readcol).

Description

Submit a simple SQL query to MySQL server, using the connection
previously opened with openmysql. Retrieve the result into
a row of variables, much as readcol does. Return dimensionality
of result(s).

Calling Sequence

mysqlquery,lun,query,[varables...],[format='(a,f,...)']

Inputs

lun - The logical unit of the pipe (opened by openmysql).
query - String (or array of strings) to send to pipe.

Optional Input Parameters

Keyword Input Parameters

format - Specify format of output variables (default is ascii).
cmd - Flag indicating this is a command, not a query so
don't bother processing the output (but do report the
number of rows affected/warnings? - not implimented).
verbose - Flag turns on debugging output to standard out.

Outputs

variables - A list of variables to recieve columns of output.
Default type is ascii, but use the format keyword to
specify other data types.

Keyword Output Parameters

HEADS - String to receive array of column heads.
NGOOD - Number of valid lines found that were read.

Common Blocks

Side Effects

Restrictions

Requires an open connection to MySQL server (established by
use of openmysql) as well as valid permissions for whatever
query or command is to be executed.

Procedure

Modification History

2002-02-14 Will Grundy, adapted from earlier version called mysql.pro
2002-02-27 WG changed behavior so 'NULL' becomes NaN instead of
making the line be ignored when it occurs in a numerical
field.
2002-03-25 WG changed to split on tab instead of white space, so that
strings with internal spaces (but not tabs) can be retrieved.
2003/01/10, MWB, fixed multi-line query error. Only one query per
call is allowed.
2006/11/09, PLC, changed strsplit call to use /preserve_null flag
this means a field can now return an empty string.
The behavior for non-'a' type fields is not defined
in this case.
2007/07/15, MWB, added NGOOD output keyword
2010/03/11, MWB, change behavior so that if there is only one valid
line the result is returned as a scalar instead of
a one-element vector.
2014/03/07, MWB, increased number of returned variables to 35.
2016/11/14, MWB, fix to LL format code handling, propagated from readcol
BUGS/WISH LIST:
Ought to verify connection to MySQL server.
Does nothing helpful with SQL command results.
Does nothing helpful to identify/report bad SQL syntax.