/* * Program type: API Interface * * Desription: * This program demonstrates the reallocation of SQLDA * and the 'isc_dsql_describe' statement. After a query * is examined with 'isc_dsql_describe', an SQLDA of correct * size is reallocated, and some information is printed about * the query: its type (select, non-select), the number * of columns, etc. * The contents of this file are subject to the Interbase Public * License Version 1.0 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy * of the License at http://www.Inprise.com/IPL.html * * Software distributed under the License is distributed on an * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express * or implied. See the License for the specific language governing * rights and limitations under the License. * * The Original Code was created by Inprise Corporation * and its predecessors. Portions created by Inprise Corporation are * Copyright (C) Inprise Corporation. * * All Rights Reserved. * Contributor(s): ______________________________________. */ #include <stdlib.h> #include <string.h> #include <ibase.h> #include <stdio.h> #include "example.h" char *sel_str = "SELECT department, mngr_no, location, head_dept \ FROM department WHERE head_dept in ('100', '900', '600')"; isc_db_handle DB = 0; /* database handle */ isc_tr_handle trans = 0; /* transaction handle */ ISC_STATUS_ARRAY status; /* status vector */ int main (int argc, char** argv) { int num_cols, i; isc_stmt_handle stmt = NULL; XSQLDA *sqlda; char empdb[128]; if (argc > 1) strcpy(empdb, argv[1]); else strcpy(empdb, "employee.fdb"); if (isc_attach_database(status, 0, empdb, &DB, 0, NULL)) { ERREXIT(status, 1) } /* Allocate SQLDA of an arbitrary size. */ sqlda = (XSQLDA *) malloc(XSQLDA_LENGTH(3)); sqlda->sqln = 3; sqlda->version = 1; if (isc_start_transaction(status, &trans, 1, &DB, 0, NULL)) { ERREXIT(status, 1) } /* Allocate a statement. */ if (isc_dsql_allocate_statement(status, &DB, &stmt)) { ERREXIT(status, 1) } /* Prepare the statement. */ if (isc_dsql_prepare(status, &trans, &stmt, 0, sel_str, 1, sqlda)) { ERREXIT(status, 1) } /* Describe the statement. */ if (isc_dsql_describe(status, &stmt, 1, sqlda)) { ERREXIT(status, 1) } /* This is a select statement, print more information about it. */ printf("Query Type: SELECT\n\n"); num_cols = sqlda->sqld; printf("Number of columns selected: %d\n", num_cols); /* Reallocate SQLDA if necessary. */ if (sqlda->sqln < sqlda->sqld) { sqlda = (XSQLDA *) malloc(XSQLDA_LENGTH(num_cols)); sqlda->sqln = num_cols; sqlda->version = 1; /* Re-describe the statement. */ if (isc_dsql_describe(status, &stmt, 1, sqlda)) { ERREXIT(status, 1) } num_cols = sqlda->sqld; } /* List column names, types, and lengths. */ for (i = 0; i < num_cols; i++) { printf("\nColumn name: %s\n", sqlda->sqlvar[i].sqlname); printf("Column type: %d\n", sqlda->sqlvar[i].sqltype); printf("Column length: %d\n", sqlda->sqlvar[i].sqllen); } if (isc_dsql_free_statement(status, &stmt, DSQL_drop)) { ERREXIT(status, 1) } if (isc_commit_transaction(status, &trans)) { ERREXIT(status, 1) } if (isc_detach_database(status, &DB)) { ERREXIT (status, 1) } free(sqlda); return 0; }