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>pg_select</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN926"
></A
><H2
>Name</H2
>pg_select&nbsp;--&nbsp;loop over the result of a query<A
NAME="IX-PGTCL-PGSELECT-2"
></A
></DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN931"
></A
><H2
>Synopsis</H2
><PRE
CLASS="SYNOPSIS"
>pg_select <VAR
CLASS="PARAMETER"
>conn</VAR
> <VAR
CLASS="PARAMETER"
>commandString</VAR
> <VAR
CLASS="PARAMETER"
>arrayVar</VAR
> <VAR
CLASS="PARAMETER"
>procedure</VAR
></PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN937"
></A
><H2
>Description</H2
><P
>   <CODE
CLASS="FUNCTION"
>pg_select</CODE
> submits a query
   (<TT
CLASS="COMMAND"
>SELECT</TT
> statement) to the
   <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
> server and executes a given
   chunk of code for each row in the result.  The
   <VAR
CLASS="PARAMETER"
>commandString</VAR
> must be a
   <TT
CLASS="COMMAND"
>SELECT</TT
> statement; anything else returns an
   error.  The <VAR
CLASS="PARAMETER"
>arrayVar</VAR
> variable is an array
   name used in the loop.  For each row,
   <VAR
CLASS="PARAMETER"
>arrayVar</VAR
> is filled in with the row values,
   using the column names as the array indices.  Then the
   <VAR
CLASS="PARAMETER"
>procedure</VAR
> is executed.
  </P
><P
>   In addition to the column values, the following special entries are
   made in the array:

   <P
></P
></P><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>.headers</TT
></DT
><DD
><P
>       A list of the column names returned by the query.
      </P
></DD
><DT
><TT
CLASS="LITERAL"
>.numcols</TT
></DT
><DD
><P
>       The number of columns returned by the query.
      </P
></DD
><DT
><TT
CLASS="LITERAL"
>.tupno</TT
></DT
><DD
><P
>       The current row number, starting at zero and incrementing for
       each iteration of the loop body.
      </P
></DD
></DL
></DIV
><P>
  </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN965"
></A
><H2
>Arguments</H2
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><VAR
CLASS="PARAMETER"
>conn</VAR
></DT
><DD
><P
>      The handle of the connection on which to execute the query.
     </P
></DD
><DT
><VAR
CLASS="PARAMETER"
>commandString</VAR
></DT
><DD
><P
>      The SQL query to execute.
     </P
></DD
><DT
><VAR
CLASS="PARAMETER"
>arrayVar</VAR
></DT
><DD
><P
>      An array variable for returned rows.
     </P
></DD
><DT
><VAR
CLASS="PARAMETER"
>procedure</VAR
></DT
><DD
><P
>      The procedure to run for each returned row.
     </P
></DD
></DL
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN988"
></A
><H2
>Return Value</H2
><P
>   None
  </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN991"
></A
><H2
>Examples</H2
><P
>   This examples assumes that the table <CODE
CLASS="CLASSNAME"
>table1</CODE
> has
   columns <TT
CLASS="STRUCTFIELD"
>control</TT
> and <TT
CLASS="STRUCTFIELD"
>name</TT
> (and
   perhaps others):
</P><PRE
CLASS="PROGRAMLISTING"
>pg_select $pgconn "SELECT * FROM table1;" array {
    puts [format "%5d %s" $array(control) $array(name)]
}</PRE
><P>
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