esp_query

Syntax

esp_query -p host:port/workspace/project -c user[:password] [OPTION...]

Required Arguments

• -c user[:password] – authenticates access to an ESP server with a user ID and, optionally, a password. If you do not provide either the password or the -k or -G option, you are prompted for the password. If the Event Stream Processor successfully authenticates with these credentials, the connection is maintained, otherwise the Event Stream Processor immediately closes the connection.
• -p host:port/workspace/project – Together, the host:port/workspace/project arguments specify the URI to connect to the ESP Server (cluster manager). For example, if you have started your ESP cluster server on port 19011 of your local machine, and you are running a project called prj1 in the default workspace, specify -p as: -p localhost:19011/default/prj1

Options

• -e – Specifies that an encrypted SSL connection to the Event Stream Processor should be used.
• -G – (optional) authenticates access to the Event Stream Processor with credentials held within a Kerberos authentication ticket. Environment variables determine where the system will look to find authentication tickets (See Administrators Guide > Security in the Event Stream Processor > Authentication > Setting Environment Variables for Kerberos for more information). If the user name differs from the default principal name in the ticket cache, specify an alternate user name with the –c option to use the corresponding authentication ticket.
• -h – Prints a list of possible options on the screen along with a brief explanation for each option.
• -k <path> – Performs authentication by using the RSA private key file mechanism instead of password authentication. The privateRsaKeyFile must specify the pathname of the private RSA key file. Ensure that the ESP Server has been started with the -k option specifying the directory in which to store the RSA keys.
  Note: With this option enabled, the user name must be specified with the -c option, but the password is not required.
• -m <date format> – Sets the format for date values using strptime format. The default is "%Y-%m-%d %H:%M:%S+00".
• -P <precision> – Specifies the number of decimal places in output (default 2).
• -Q <query> – Specifies the query to execute (if not provided via stdin).
• -q hostname:port – Specifies the port, or both the hostname and port, of the SQL Listener of the target ESP Server. The default host is "localhost" and the default port is "22200".
• -t <table name> – Specifies the name of the table for the XML output. The default name is "Result".
• -v – Prints the esp_query utility version.

Usage

esp_query accepts an SQL query on the standard input and forwards it to a running instance of the Event Stream Processor. It then prints the results of the query on the standard output.

From a UNIX or Linux command line prompt, or the Query panel in the ESP Studio, the SQL query must be enclosed in double quotes. From a DOS command line prompt, double quotes must not enclose the SQL query.

Querying streams doesn't make sense, but the esp_query can be used to obtain information from an error stream if a downstream window is defined to retain the state of the error stream.

Examples

To print the contents of stream Emp, on a UNIX machine named myhost, using SQL port 11100:

echo "select * from Emp" | ./esp_query -p myhost:11100/workspace/project -c user:password

If myhost is a Windows machine, the esp_query syntax is the same, but the query must not be in quotes:

echo select * from Emp | esp_query -p myhost:11100/workspace/project  -c user:password

To delete an entry from the Dept stream and update the Emp stream accordingly:

echo "delete from Dept where dn='SWP'; update Emp set dn='' where dn='SWP'" | ./esp_query -p myhost:11100/workspace/project -c user:password

To query a window, named ErrorState, that retains the state of an error stream named ErrorStream:

echo "select e.*, recordDataToString(e.sourceStreamName, e.errorRecord ) errorRecord from errorState e" |esp_query -p myhost:11100/workspace/project -c user:password