Data structure that represents a result from a query. More...

#include "db_key.h"
#include "db_val.h"

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Data Structures

struct db1_res
This type represents a result returned by db_query function (see below). More...

Defines

#define RES_COL_N(re) ((re)->col.n)
Return the number of columns.
#define RES_LAST_ROW(re) ((re)->last_row)
Return the last row of the result.
#define RES_NAMES(re) ((re)->col.names)
Return the column names.
#define RES_NUM_ROWS(re) ((re)->res_rows)
Return the number of total result rows.
#define RES_ROW_N(re) ((re)->n)
Return the number of current result rows.
#define RES_ROWS(re) ((re)->rows)
Return the result rows.
#define RES_TYPES(re) ((re)->col.types)
Return the column types.

Typedefs

typedef struct db1_res db1_res_t
This type represents a result returned by db_query function (see below).

Functions

int db_allocate_columns (db1_res_t *_r, const unsigned int cols)
Allocate storage for column names and type in existing result structure.
int db_allocate_rows (db1_res_t *_res)
Allocate memory for rows.
int db_free_columns (db1_res_t *_r)
Release memory used by columns.
int db_free_result (db1_res_t *_r)
Release memory used by a result structure.
int db_free_rows (db1_res_t *_r)
Release memory used by rows in a result structure.
db1_res_t * db_new_result (void)
Create a new result structure and initialize it.

Detailed Description

Data structure that represents a result from a database query, it also provides some convenience macros and some memory management functions for result structures.

Definition in file srdb1/db_res.h.

Typedef Documentation

typedef struct db1_res db1_res_t

The result can consist of zero or more rows (see db_row_t description).

Note: A variable of type db1_res_t returned by db_query function uses dynamicaly allocated memory, don't forget to call db_free_result if you don't need the variable anymore. You will encounter memory leaks if you fail to do this!

In addition to zero or more rows, each db1_res_t object contains also an array of db_key_t objects. The objects represent keys (names of columns). *

Function Documentation

int db_allocate_columns	(	db1_res_t *	_r,
		const unsigned int	cols
	)			`[inline]`

If no more memory is available for the allocation of the types then the already allocated memory for the names is freed.

Parameters:

	_r	filled result set
	cols	number of columns

Returns:: zero on success, negative on errors

Definition at line 146 of file srdb1/db_res.c.

References RES_NAMES, and RES_TYPES.

Referenced by db_mysql_get_columns(), and db_postgres_get_columns().

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int db_allocate_rows ( db1_res_t * _res ) [inline]

Parameters:

_res

result set

Returns:: zero on success, negative on errors

Definition at line 176 of file srdb1/db_res.c.

References RES_ROW_N, and RES_ROWS.

Referenced by db_mysql_convert_rows(), and db_postgres_convert_rows().

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int db_free_columns ( db1_res_t * _r ) [inline]

This methods assumes that the string values holding the column names are in memory allocated from the database driver, and thus must be not freed here.

Parameters:

_r

the result that should be released