upd_stats -	Generate and perform UPDATE STATISTICS on Informix tables
  Usage:
    upd_stats [-p <file>] [-d <dbname>] [-[t][h|m|l[d]]] [-c[h|m|l|n]|-nc]
    	[-f <file>] [tabname [...]]

  Options:
    -p <file>
    	File to output script to.  When this option is used, a script of SQL
	commands is generated, but the commands are not run.
    -d <dbname>
	Database to execute script against.  If unset, the environment variable
	DBNAME will be used.  If DBNAME is unset, execution will stop.
    -[t][h|m|l[d]]]
        Mode to use for TABLE.  The initial 't' character is optional, to
	provide backwards compatibility with previous versions of upd_stats.
	Modes are H=High, M=Medium, L=Low or LD=Low Drop Distributions.
    -c[h|m|l|n]|-nc
        Mode to use for COLUMN(S).  This applies to all columns which form
	part of an index on the table(s).  Modes are H=High, M=Medium, L=Low or
	N=None.  -cn or -nc can be used to specify no statistics on columns.
    -f <file>
    	Read the list of tables to perform statistics for from this file.  Only
	one filename is accepted, but "-" can be used to read from STDIN.
	Subsequent arguments are assumed to be explicit table-names.
    tabname
        Explicit table-name(s) or reg-exp(s) (using SQL MATCHES syntax) to
	identify the tables to have statistics created.  If no tabname is
	given, ALL user tables (not the system catalogs) will be done.

  Notes:
  	If no mode parameters are provided, the environment variable UPD_STATS
	is used.  If UPD_STATS is set, it should be in the format
		<table-mode>:<col-mode>
	eg: "M:H" or "LD:N" (UPD_STATS is case-insensitive).  If UPD_STATS is
	unset or invalid, the default mode is Low for Tables, None for Columns.