pgr_point_input.h File Reference

#include <stddef.h>
#include "c_types/pgr_point_t.h"

Include dependency graph for pgr_point_input.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Functions
void	pgr_point_input (char *points_sql, Pgr_point_t **points, size_t *pointsTotal)
	pgr_point_input More...

Function Documentation

pgr_point_input()

void pgr_point_input	(	char *	points_sql,
		Pgr_point_t **	points,
		size_t *	pointsTotal
	)

pgr_point_input

For queries of the type:

SELECT x, y
FROM ...

Parameters

[in]	points_sql
[out]	points
[out]	pointsTotal	pgr_point_input

Definition at line 48 of file pgr_point_input.c.

                             {
    clock_t start_t = clock();
 
    const int tuple_limit = 1000000;
 
    size_t total_tuples = 0;
 
    Column_info_t info[3];
 
    int i;
    for (i = 0; i < 2; ++i) {
        info[i].colNumber = -1;
        info[i].type = 0;
        info[i].strict = true;
        info[i].eType = ANY_NUMERICAL;
    }
    info[0].name = "x";
    info[1].name = "y";
 
 
    void *SPIplan;
    SPIplan = pgr_SPI_prepare(points_sql);
 
    Portal SPIportal;
    SPIportal = pgr_SPI_cursor_open(SPIplan);
 
 
    bool moredata = true;
    (*pointsTotal) = total_tuples;
 
    while (moredata == true) {
        SPI_cursor_fetch(SPIportal, true, tuple_limit);
        if (total_tuples == 0)
            pgr_fetch_column_info(info, 2);
 
        size_t ntuples = SPI_processed;
        total_tuples += ntuples;
 
        if (ntuples > 0) {
            if ((*points) == NULL)
                (*points) = (Pgr_point_t *)
                    palloc0(total_tuples * sizeof(Pgr_point_t));
            else
                (*points) = (Pgr_point_t *)
                    repalloc((*points),
                            total_tuples * sizeof(Pgr_point_t));
 
            if ((*points) == NULL) {
                elog(ERROR, "Out of memory");
            }
 
            SPITupleTable *tuptable = SPI_tuptable;
            TupleDesc tupdesc = SPI_tuptable->tupdesc;
 
            size_t t;
            for (t = 0; t < ntuples; t++) {
                HeapTuple tuple = tuptable->vals[t];
                pgr_fetch_row(&tuple, &tupdesc, info,
                        &(*points)[total_tuples - ntuples + t]);
            }
            SPI_freetuptable(tuptable);
        } else {
            moredata = false;
        }
    }
 
    SPI_cursor_close(SPIportal);
 
 
    if (total_tuples == 0) {
        (*pointsTotal) = 0;
        return;
    }
 
    (*pointsTotal) = total_tuples;
    time_msg(" reading points:", start_t, clock());
}

References ANY_NUMERICAL, Column_info_t::colNumber, Column_info_t::eType, Column_info_t::name, pgr_fetch_column_info(), pgr_fetch_row(), pgr_SPI_cursor_open(), pgr_SPI_prepare(), Column_info_t::strict, time_msg(), and Column_info_t::type.