Embedding SQLite in a c programm
Embedding SQLite in a c programm
The following program demonstrates how to embed SQLite into a c program.
I compiled the program with MinGW without any problems (Using this makefile)
In order to compile the program, you have to download the SQLite sources (version 3.0.1, the zip file) as well as the following c program (embed_sqlite.c). I don't know how easy or hard it is to compile it with another compiler than MinGW.
The program does the following:
Creates a database (filename: countries.db).
Creates a table in this database (table name: countries).
Inserts many countries with their size and population.
Queries the table for the countries with the most/fewest people/area.
The programm
embed_sqlite.c
#include <string.h>
#include <stdio.h>
#include "sqlite3.h"
sqlite3* db;
int first_row;
int select_callback(void *p_data, int num_fields, char **p_fields, char **p_col_names) {
int i;
int *p_rn = (int*)p_data;
if (first_row) {
first_row = 0;
for(i=0; i < num_fields; i++) {
printf("%20s", p_col_names[i]);
}
printf("\n");
for(i=0; i< num_fields*20; i++) {
printf("=");
}
printf("\n");
}
(*p_rn)++;
for(i=0; i < num_fields; i++) {
printf("%20s", p_fields[i]);
}
printf("\n");
return 0;
}
void select_stmt(const char* stmt) {
char *errmsg;
int ret;
int nrecs = 0;
first_row = 1;
ret = sqlite3_exec(db, stmt, select_callback, &nrecs, &errmsg);
if(ret!=SQLITE_OK) {
printf("Error in select statement %s [%s].\n", stmt, errmsg);
}
else {
printf("\n %d records returned.\n", nrecs);
}
}
void sql_stmt(const char* stmt) {
char *errmsg;
int ret;
ret = sqlite3_exec(db, stmt, 0, 0, &errmsg);
if(ret != SQLITE_OK) {
printf("Error in statement: %s [%s].\n", stmt, errmsg);
}
}
void insert_countries() {
sql_stmt("begin");
sql_stmt("insert into countries values ('Afghanistan' , 251826, 22664136)");
sql_stmt("insert into countries values ('Albania' , 11100, 3249136)");
sql_stmt("insert into countries values ('Algeria' , 919595, 29183032)");
sql_stmt("insert into countries values ('Andorra' , 175, 67509)");
sql_stmt("insert into countries values ('Angola' , 481354, 10342899)");
sql_stmt("insert into countries values ('Argentina' , 1073400, 34672997)");
sql_stmt("insert into countries values ('Armenia' , 11506, 3463574)");
sql_stmt("insert into countries values ('Australia' , 2966155, 18260863)");
sql_stmt("insert into countries values ('Austria' , 32377, 8013614)");
sql_stmt("insert into countries values ('Azerbaijan' , 33436, 7676953)");
sql_stmt("insert into countries values ('Bahrain' , 267, 590042)");
sql_stmt("insert into countries values ('Bangladesh' , 55598, 123062800)");
sql_stmt("insert into countries values ('Barbados' , 166, 257030)");
sql_stmt("insert into countries values ('Belarus' , 80155, 10415973)");
sql_stmt("insert into countries values ('Belgium' , 11783, 10131863)");
sql_stmt("insert into countries values ('Belize' , 8866, 219296)");
sql_stmt("insert into countries values ('Benin' , 43475, 5709529)");
sql_stmt("insert into countries values ('Bhutan' , 18200, 1822625)");
sql_stmt("insert into countries values ('Bolivia' , 424165, 7165257)");
sql_stmt("insert into countries values ('Bosnia-Herzegovina' , 19741, 2656240)");
sql_stmt("insert into countries values ('Botswana' , 231800, 1477630)");
sql_stmt("insert into countries values ('Brazil' , 3286488, 162661214)");
sql_stmt("insert into countries values ('Brunei' , 2226, 299939)");
sql_stmt("insert into countries values ('Bulgaria' , 42823, 8612757)");
sql_stmt("insert into countries values ('Burkina Faso' , 105869, 10623323)");
sql_stmt("insert into countries values ('Burundi' , 10745, 5943057)");
sql_stmt("insert into countries values ('Cambodia' , 69898, 10600000)");
sql_stmt("insert into countries values ('Cameroon' , 183569, 14261557)");
sql_stmt("insert into countries values ('Canada' , 3849674, 29857369)");
sql_stmt("insert into countries values ('Cape Verde' , 1557, 449066)");
sql_stmt("insert into countries values ('Central African Republic' , 240535, 3274426)");
sql_stmt("insert into countries values ('Chad' , 495755, 6976845)");
sql_stmt("insert into countries values ('Chile' , 292135, 14333258)");
sql_stmt("insert into countries values ('China' , 3689631, 1210004956)");
sql_stmt("insert into countries values ('Colombia' , 440831, 36813161)");
sql_stmt("insert into countries values ('Comoros' , 863, 569237)");
sql_stmt("insert into countries values ('Congo(Zaire)' , 905446, 46498539)");
sql_stmt("insert into countries values ('Congo Republic' , 132047, 2527841)");
sql_stmt("insert into countries values ('Costa Rica' , 19730, 3463083)");
sql_stmt("insert into countries values ('Croatia' , 21829, 5004112)");
sql_stmt("insert into countries values ('Cuba' , 42804, 11007446)");
sql_stmt("insert into countries values ('Cyprus' , 3593, 736636)");
sql_stmt("insert into countries values ('Czech Republic' , 30613, 10321120)");
sql_stmt("insert into countries values ('Denmark' , 16638, 5210833)");
sql_stmt("insert into countries values ('Djibouti' , 8958, 427642)");
sql_stmt("insert into countries values ('Dominica' , 305, 82926)");
sql_stmt("insert into countries values ('Dominican Republic' , 18704, 8088881)");
sql_stmt("insert into countries values ('Ecuador' , 109484, 11466291)");
sql_stmt("insert into countries values ('Egypt' , 386662, 65375107)");
sql_stmt("insert into countries values ('El Salvador' , 8124, 5828987)");
sql_stmt("insert into countries values ('Equatorial Guinea' , 10831, 431282)");
sql_stmt("insert into countries values ('Eritrea' , 45300, 3909628)");
sql_stmt("insert into countries values ('Estonia' , 17413, 1459428)");
sql_stmt("insert into countries values ('Ethiopia' , 483123, 57171682)");
sql_stmt("insert into countries values ('Fiji' , 7078, 782381)");
sql_stmt("insert into countries values ('Finland' , 130559, 5100213)");
sql_stmt("insert into countries values ('France' , 211208, 58317450)");
sql_stmt("insert into countries values ('Gabon' , 103347, 1172798)");
sql_stmt("insert into countries values ('Gambia' , 4127, 1020178)");
sql_stmt("insert into countries values ('Georgia' , 26911, 5219810)");
sql_stmt("insert into countries values ('Germany' , 137882, 83536115)");
sql_stmt("insert into countries values ('Ghana' , 92098, 17698271)");
sql_stmt("insert into countries values ('Greece' , 50962, 10718518)");
sql_stmt("insert into countries values ('Grenada' , 133, 94961)");
sql_stmt("insert into countries values ('Guatemala' , 42042, 11177614)");
sql_stmt("insert into countries values ('Guinea' , 94926, 7411981)");
sql_stmt("insert into countries values ('Guinea-Bissau' , 13948, 1151330)");
sql_stmt("insert into countries values ('Guyana' , 83000, 712091)");
sql_stmt("insert into countries values ('Haiti' , 10714, 6731539)");
sql_stmt("insert into countries values ('Honduras' , 43277, 5605193)");
sql_stmt("insert into countries values ('Hungary' , 35920, 10002541)");
sql_stmt("insert into countries values ('Iceland' , 36769, 268369)");
sql_stmt("insert into countries values ('India' , 1237062, 952107694)");
sql_stmt("insert into countries values ('Indonesia' , 742410, 206611600)");
sql_stmt("insert into countries values ('Iran' , 632457, 66094264)");
sql_stmt("insert into countries values ('Iraq' , 169235, 21422292)");
sql_stmt("insert into countries values ('Ireland' , 27137, 3562902)");
sql_stmt("insert into countries values ('Israel' , 8019, 5215022)");
sql_stmt("insert into countries values ('Italy' , 116234, 57460274)");
sql_stmt("insert into countries values ('Ivory Coast' , 124518, 14762445)");
sql_stmt("insert into countries values ('Jamaica' , 4244, 2593918)");
sql_stmt("insert into countries values ('Japan' , 145870, 125568504)");
sql_stmt("insert into countries values ('Jordan' , 35135, 4212152)");
sql_stmt("insert into countries values ('Kazakhstan' , 1049156, 16916463)");
sql_stmt("insert into countries values ('Kenya' , 224961, 28176686)");
sql_stmt("insert into countries values ('KoreaNorth' , 46540, 23904124)");
sql_stmt("insert into countries values ('KoreaSouth' , 38230, 45482291)");
sql_stmt("insert into countries values ('Kuwait' , 6880, 1950047)");
sql_stmt("insert into countries values ('Kyrgyzstan' , 76641, 4529648)");
sql_stmt("insert into countries values ('Laos' , 91429, 4905772)");
sql_stmt("insert into countries values ('Latvia' , 24595, 2468982)");
sql_stmt("insert into countries values ('Lebanon' , 4015, 3776317)");
sql_stmt("insert into countries values ('Lesotho' , 11720, 1970781)");
sql_stmt("insert into countries values ('Liberia' , 38250, 2109789)");
sql_stmt("insert into countries values ('Libya' , 679362, 5445436)");
sql_stmt("insert into countries values ('Liechtenstein' , 62, 31011)");
sql_stmt("insert into countries values ('Lithuania' , 25174, 3718000)");
sql_stmt("insert into countries values ('Luxembourg' , 998, 406901)");
sql_stmt("insert into countries values ('Macedonia' , 9928, 2104035)");
sql_stmt("insert into countries values ('Madagascar' , 226658, 13670507)");
sql_stmt("insert into countries values ('Malawi' , 45747, 9542844)");
sql_stmt("insert into countries values ('Malaysia' , 129251, 19962893)");
sql_stmt("insert into countries values ('Maldives' , 115, 270758)");
sql_stmt("insert into countries values ('Mali' , 478767, 9653261)");
sql_stmt("insert into countries values ('Malta' , 122, 372314)");
sql_stmt("insert into countries values ('Mauritania' , 395956, 2336048)");
sql_stmt("insert into countries values ('Mauritius' , 788, 1139047)");
sql_stmt("insert into countries values ('Mexico' , 756066, 95772462)");
sql_stmt("insert into countries values ('Micronesia' , 271, 125377)");
sql_stmt("insert into countries values ('Moldova' , 13012, 4463847)");
sql_stmt("insert into countries values ('Mongolia' , 604829, 2496617)");
sql_stmt("insert into countries values ('Morocco' , 275114, 29779156)");
sql_stmt("insert into countries values ('Mozambique' , 308642, 17877927)");
sql_stmt("insert into countries values ('Myanmar (Burma)' , 261228, 49975625)");
sql_stmt("insert into countries values ('Namibia' , 317818, 1677243)");
sql_stmt("insert into countries values ('Nepal' , 56827, 22094033)");
sql_stmt("insert into countries values ('Netherlands' , 16133, 15531940)");
sql_stmt("insert into countries values ('New Zealand' , 103519, 3547983)");
sql_stmt("insert into countries values ('Nicaragua' , 50054, 4272352)");
sql_stmt("insert into countries values ('Niger' , 489191, 9113001)");
sql_stmt("insert into countries values ('Nigeria' , 356669, 103912489)");
sql_stmt("insert into countries values ('Norway' , 125050, 4345941)");
sql_stmt("insert into countries values ('Oman' , 82030, 2186548)");
sql_stmt("insert into countries values ('Pakistan' , 310432, 129275660)");
sql_stmt("insert into countries values ('Panama' , 29157, 2655094)");
sql_stmt("insert into countries values ('Papua New Guinea' , 178704, 4394537)");
sql_stmt("insert into countries values ('Paraguay' , 157048, 5504146)");
sql_stmt("insert into countries values ('Peru' , 496225, 24523408)");
sql_stmt("insert into countries values ('Philippines' , 115831, 74480848)");
sql_stmt("insert into countries values ('Poland' , 120728, 38642565)");
sql_stmt("insert into countries values ('Portugal' , 35516, 9865114)");
sql_stmt("insert into countries values ('Qatar' , 4416, 547761)");
sql_stmt("insert into countries values ('Romania' , 91699, 21657162)");
sql_stmt("insert into countries values ('Russia' , 6592849, 148190419)");
sql_stmt("insert into countries values ('Rwanda' , 10169, 6853359)");
sql_stmt("insert into countries values ('St. Kitts and Nevis' , 104, 41369)");
sql_stmt("insert into countries values ('St. Lucia' , 238, 157862)");
sql_stmt("insert into countries values ('St. Vincent/Grenadines' , 150, 118344)");
sql_stmt("insert into countries values ('S�o Tomé and Principe' , 372, 144128)");
sql_stmt("insert into countries values ('Saudi Arabia ' , 830000, 19409058)");
sql_stmt("insert into countries values ('Senegal' , 75951, 9092749)");
sql_stmt("insert into countries values ('Seychelles' , 175, 77575)");
sql_stmt("insert into countries values ('Sierra Leone' , 27925, 4793121)");
sql_stmt("insert into countries values ('Singapore' , 246, 3396924)");
sql_stmt("insert into countries values ('Slovakia' , 18933, 5374362)");
sql_stmt("insert into countries values ('Slovenia' , 7819, 1951433)");
sql_stmt("insert into countries values ('Solomon Islands' , 10954, 412902)");
sql_stmt("insert into countries values ('Somalia' , 246201, 9369151)");
sql_stmt("insert into countries values ('South Africa' , 433680, 41743459)");
sql_stmt("insert into countries values ('Spain' , 194885, 38853397)");
sql_stmt("insert into countries values ('Sri Lanka' , 24962, 18553074)");
sql_stmt("insert into countries values ('Sudan' , 967500, 31065229)");
sql_stmt("insert into countries values ('Suriname' , 63251, 436418)");
sql_stmt("insert into countries values ('Swaziland' , 6704, 998730)");
sql_stmt("insert into countries values ('Sweden' , 173732, 8861270)");
sql_stmt("insert into countries values ('Switzerland' , 15943, 7124745)");
sql_stmt("insert into countries values ('Syria' , 71498, 15608648)");
sql_stmt("insert into countries values ('Taiwan' , 13900, 21304000)");
sql_stmt("insert into countries values ('Tajikistan' , 55251, 5916373)");
sql_stmt("insert into countries values ('Tanzania' , 364900, 29058470)");
sql_stmt("insert into countries values ('Thailand' , 198115, 58851357)");
sql_stmt("insert into countries values ('Togo' , 21925, 4570530)");
sql_stmt("insert into countries values ('Trinidad and Tobago' , 1980, 1272385)");
sql_stmt("insert into countries values ('Tunisia' , 63170, 9019687)");
sql_stmt("insert into countries values ('Turkey' , 300948, 62484478)");
sql_stmt("insert into countries values ('Turkmenistan' , 188456, 4149263)");
sql_stmt("insert into countries values ('Uganda' , 93104, 20158176)");
sql_stmt("insert into countries values ('Ukraine' , 233090, 50864009)");
sql_stmt("insert into countries values ('United Arab Emirates' , 32278, 3057337)");
sql_stmt("insert into countries values ('United Kingdom' , 94248, 58489975)");
sql_stmt("insert into countries values ('United States' , 3787425, 265089998)");
sql_stmt("insert into countries values ('Uruguay' , 68500, 3238952)");
sql_stmt("insert into countries values ('Uzbekistan' , 172742, 23418381)");
sql_stmt("insert into countries values ('Venezuela' , 352145, 21983188)");
sql_stmt("insert into countries values ('Vietnam' , 128066, 73976973)");
sql_stmt("insert into countries values ('Yemen' , 205356, 13483178)");
sql_stmt("insert into countries values ('Yugoslavia (Serbia-Montenegro)', 26913, 10611558)");
sql_stmt("insert into countries values ('Zambia' , 290586, 9159072)");
sql_stmt("insert into countries values ('Zimbabwe' , 150873, 11271314)");
sql_stmt("commit");
}
int main() {
sqlite3_open("./countries.db", &db);
if(db == 0) {
printf("Could not open database.");
return 1;
}
sql_stmt("create table countries (country_name, size_sq_miles, population)");
insert_countries();
printf("\nselecting the countries with the largest population\n\n");
select_stmt("select * from countries order by population desc limit 5");
printf("\nselecting the countries with the smallest population\n\n");
select_stmt("select * from countries order by population asc limit 5");
printf("\nselecting the countries with the largest area\n\n");
select_stmt("select * from countries order by size_sq_miles desc limit 5");
printf("\nselecting the countries with the smallest area\n\n");
select_stmt("select * from countries order by size_sq_miles asc limit 5");
sqlite3_close(db);
return 0;
}
The makefile
The makefile is very rudimentary as I expect most .c files (except embed_sqlite.c) to be compiled only once.
makefile
CC_OPTS=-Wall
embed_sqlite.exe : embed_sqlite.o \
attach.o \
auth.o \
build.o \
btree.o \
date.o \
delete.o \
expr.o \
func.o \
hash.o \
insert.o \
legacy.o \
main.o \
opcodes.o \
os_win.o \
pager.o \
parse.o \
pragma.o \
printf.o \
random.o \
select.o \
table.o \
tokenize.o \
trigger.o \
update.o \
util.o \
utf.o \
vacuum.o \
vdbe.o \
vdbeapi.o \
vdbemem.o \
vdbeaux.o \
where.o
gcc embed_sqlite.o \
attach.o \
auth.o \
build.o \
btree.o \
date.o \
delete.o \
expr.o \
func.o \
hash.o \
insert.o \
legacy.o \
main.o \
opcodes.o \
os_win.o \
pager.o \
parse.o \
pragma.o \
printf.o \
random.o \
select.o \
table.o \
tokenize.o \
trigger.o \
update.o \
util.o \
utf.o \
vacuum.o \
vdbe.o \
vdbeapi.o \
vdbemem.o \
vdbeaux.o \
where.o -o $@
embed_sqlite.o : embed_sqlite.c
gcc $(CC_OPTS) -c embed_sqlite.c
legacy.o : legacy.c
gcc $(CC_OPTS) -c legacy.c
main.o : main.c
gcc $(CC_OPTS) -c main.c
attach.o : attach.c
gcc $(CC_OPTS) -c attach.c
auth.o : auth.c
gcc $(CC_OPTS) -c auth.c
btree.o : btree.c btree.h
gcc $(CC_OPTS) -c btree.c
build.o : build.c
gcc $(CC_OPTS) -c build.c
date.o : date.c
gcc $(CC_OPTS) -c date.c
delete.o : delete.c
gcc $(CC_OPTS) -c delete.c
expr.o : expr.c
gcc $(CC_OPTS) -c expr.c
func.o : func.c
gcc $(CC_OPTS) -c func.c
hash.o : hash.c hash.h
gcc $(CC_OPTS) -c hash.c
insert.o : insert.c
gcc $(CC_OPTS) -c insert.c
opcodes.o : opcodes.c opcodes.h
gcc $(CC_OPTS) -c opcodes.c
os_win.o : os_win.c os_win.h
gcc $(CC_OPTS) -c os_win.c
pager.o : pager.c pager.h
gcc $(CC_OPTS) -c pager.c
parse.o : parse.c parse.h
gcc $(CC_OPTS) -c parse.c
pragma.o : pragma.c
gcc $(CC_OPTS) -c pragma.c
printf.o : printf.c
gcc $(CC_OPTS) -c printf.c
random.o : random.c
gcc $(CC_OPTS) -c random.c
select.o : select.c
gcc $(CC_OPTS) -c select.c
#shell.o : shell.c
# gcc $(CC_OPTS) -c shell.c
table.o : table.c
gcc $(CC_OPTS) -c table.c
tokenize.o : tokenize.c
gcc $(CC_OPTS) -c tokenize.c
trigger.o : trigger.c
gcc $(CC_OPTS) -c trigger.c
update.o : update.c
gcc $(CC_OPTS) -c update.c
util.o : util.c
gcc $(CC_OPTS) -c util.c
utf.o : utf.c
gcc $(CC_OPTS) -c utf.c
vacuum.o : vacuum.c
gcc $(CC_OPTS) -c vacuum.c
vdbe.o : vdbe.c vdbe.h
gcc $(CC_OPTS) -c vdbe.c
vdbeapi.o : vdbeapi.c
gcc $(CC_OPTS) -c vdbeapi.c
vdbemem.o : vdbemem.c
gcc $(CC_OPTS) -c vdbemem.c
vdbeaux.o : vdbeaux.c
gcc $(CC_OPTS) -c vdbeaux.c
where.o : where.c
gcc $(CC_OPTS) -c where.c
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