TIMPORT - general purpose data import

SYNOPSIS

<TIMPORT [options] $schema [FROMFILE] $data|$file[ /]>
[  ... statements ...
</TIMPORT>]


DESCRIPTION
The <TIMPORT> statement (Texis IMPORT) imports text data into Vortex variables. The $schema argument is a schema (template), which defines what fields are in the source data and what format they are in.

The $data parameter is the text buffer containing raw data to be imported. If the FROMFILE flag is given, it is considered a filename instead, and that file is read for the import data.

Each value of the buffer or filename variable is imported in sequence. The returned fields are assigned to Vortex variables of the same name, one field per value. Each result row returned by <TIMPORT> adds another set of values to the variables, and the statements inside the <TIMPORT> block are executed. (I.e. a loop occurs for every row imported, not just for every buffer/filename given.)

Unlike the command-line version of TIMPORT, in Vortex the imported fields are not inserted into a table. Instead they are returned as variables for further processing by the Vortex script. This gives the programmer complete control over what rows go where and how. For full details on the syntax of schemas and the usage of TIMPORT in general, see the Texis manual on TIMPORT. Note that the following TIMPORT keywords do not apply in Vortex, because no table is used: host, port, user, group, pass, createtable, database, droptable, table.

The variables returned by <TIMPORT> behave like <SQL> variables (here) in that only the current iteration's return value is visible inside the loop. SKIP and MAX also behave as in <SQL>, giving the number of initial values to skip, and the maximum number of values to return. Note that in version 8 and later syntax - i.e. when the syntaxversion pragma (here) is 8 or more - return values never accumulate in looping statements. Thus the corresponding ROW flag is unneeded, and not accepted.

The flags NOVARS, OKVARS can also be used; as in a <SQL> statement, NOVARS causes no variables to actually be returned, OKVARS gives a permitted list of return variables.

The $loop and $next variables are set as in <SQL> (including for self-closing statements, in version 8.00.1645136290 20220217 and later), i.e. the current loop iteration count and next-iteration count. $indexcount is not set, however.

A BREAK statement may be given inside the loop to exit prematurely.

In version 7 and later, the statement may be self-closing (<TIMPORT ... />) instead of terminated with an end tag (</TIMPORT>). The statement is then non-looping: $loop/$next are not set iff syntax version 7 (they are in version 8.00.1645136290 20220217 and later), though SKIP/MAX are still respected. Return variables accumulate.


EXAMPLE
The following example imports fields from a Unix-style mailbox into the variables $From, $Subject, $Date and lists each message:

<$schema = "
# take multiple records from a single file:
multiple
datefmt x, dd mmm yyyy HH:MM:SS
#      name    type     tag                           default_val
field  From    varchar  />>^\RFrom\x20\P=[^\space]+   UNKNOWN
field  Subject varchar  Subject                       UNKNOWN
field  Date    date     Date
field  Body    varchar  />>^=[\alnum\-_]+:\x20=[^\n]+\n\n\P=!\nFrom\x20+
">
<TIMPORT $schema FROMFILE /tmp/mbox>
  From: $From <BR>
  Subject: $Subject <BR>
  Date: $Date <BR>
  <P> <PRE>
  $Body
  </PRE>
  <HR>
</TIMPORT>


CAVEATS
The TIMPORT statement was added in version 2.1.872500000 19970825.

Column variables returned by TIMPORT are cleared first before the loop starts, i.e. previous values are lost. However, if no rows are returned by the command, then the variables are not cleared.

The rows skipped by SKIP apply after any row(s) skipped by TIMPORT schema keywords. Thus, if columnar data (format col or csv) is imported without the keepfirst keyword, the first row is still skipped, even if SKIP is 0.

TIMPORT is not available in early Webinator Vortex versions. Only Commercial Vortex versions after Sep. 1 1997, and Webinator versions after Sep. 30 1998 contain it.

The syntaxversion pragma (here) affects this statement: e.g. in version 8 and later syntax, ROW is not permitted, and its behavior is the default if looping.


SEE ALSO
SQL, LOOP, BREAK


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