pg_sendquery

pg_sendquery — Send an SQL command to the server for asynchronous execution

Synopsis

pg_sendquery conn commandString ?param...?

Description

pg_sendquery sends a command to the PostgreSQL server and returns immediately, without waiting for the command to complete and without providing a result handle. Optional arguments can be supplied to replace parameter place-holders in the command string.

Arguments

conn

The handle of the connection on which to execute the command.

commandString

The SQL command to execute.

param...

Zero or more parameter values to bind to command string place-holders. The first argument will replace $1 in the command string, the second argument will replace $2, etc.

Return Value

None.

A Tcl error will be thrown if an error occurs.

Notes

Use pg_isbusy to see if the command is still being executed. Use pg_getresult to get the result, waiting for the command to complete if necessary. Alternatively, use pg_result_callback to register a callback command to be executed when a result is ready (that is, when pg_getresult will not block).

If optional arguments are supplied, this command becomes a simplified form of pg_sendquery_params, supporting only text-format arguments with a text-format result. The command string must include parameter place-holders $1, $2, etc. and an equal number of parameter arguments. Be sure to brace-quote or escape the parameter place-holders such as $1 in the SQL command string to protect them from Tcl variable expansion. Use of these parameters avoids the need to quote and escape values which would otherwise have to be substituted directly into the command string.

The form of this command using optional arguments for parameterized queries was added in pgtclng-1.6.0.

This command uses or emulates the PostgreSQL libpq function PQsendQuery if called without optional query parameter arguments, and the function PQsendQueryParams if called with optional query parameter arguments.

SourceForge.net Logo

This version of the manual was produced for the Pgtcl-ng Sourceforge project web service site, which requires the logo on each page.

To download a logo-free copy of the manual, see the Pgtcl-ng project downloads area.