linuxCsqlite3mysql_MySQL
<code class="hljs perl">/* ********** gcc main.c -lsqlite3 -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient ************ SQLITE_OK = 0; 返回成功 SQLITE_ERROR = 1; SQL错误或错误的数据库 SQLITE_INTERNAL = 2; An internal logic error in SQLite SQLITE_PERM = 3; 拒绝访问 SQLITE_ABORT = 4; 回调函数请求中断 SQLITE_BUSY = 5; 数据库文件被锁 SQLITE_LOCKED = 6; 数据库中的一个表被锁 SQLITE_NOMEM = 7; 内存分配失败 SQLITE_READONLY = 8; 试图对一个只读数据库进行写操作 SQLITE_INTERRUPT = 9; 由sqlite_interrupt()结束操作 SQLITE_IOERR = 10; 磁盘I/O发生错误 SQLITE_CORRUPT = 11; 数据库磁盘镜像畸形 SQLITE_NOTFOUND = 12; (Internal Only)表或记录不存在 SQLITE_FULL = 13; 数据库满插入失败 SQLITE_CANTOPEN = 14; 不能打开数据库文件 SQLITE_PROTOCOL = 15; 数据库锁定协议错误 SQLITE_EMPTY = 16; (Internal Only)数据库表为空 SQLITE_SCHEMA = 17; 数据库模式改变 SQLITE_TOOBIG = 18; 对一个表数据行过多 SQLITE_CONSTRAINT = 19; 由于约束冲突而中止 SQLITE_MISMATCH = 20; 数据类型不匹配 SQLITE_MISUSE = 21; 数据库错误使用 SQLITE_NOLFS = 22; 使用主机操作系统不支持的特性 SQLITE_AUTH = 23; 非法授权 SQLITE_FORMAT = 24; 辅助数据库格式错误 SQLITE_RANGE = 25; 2nd parameter to sqlite_bind out of range SQLITE_NOTADB = 26; 打开的不是一个数据库文件 SQLITE_ROW = 100; sqlite_step() has another row ready SQLITE_DONE = 101; sqlite_step() has finished executing *************************************************************************************************** */ #include "DB.h" gseMutex dbMutex=GSE_MUTEX_INIT; static int IsUpdateAll = 0; static int iDelCount = 0; const int FREE_NUM = 1000; static int needVacuum = 0; int DBOpen(dbClass *sqlDB, const char *sqlName, char *localhost, char *user, char *password) { if(sqlDB == NULL || sqlName == NULL || 0 == strlen(sqlName)) { gseLog(L_ERROR,"NULL *p"); return -1; } int ret = 0; if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; localhost = NULL; user = NULL; password = NULL; char sqlPathName[64]={0}; sprintf(sqlPathName, "%s", sqlName); ret = sqlite3_open(sqlPathName, (struct sqlite3 **)&(sqlDB->db)); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, Cannot open db: %s",ret,sqlite3_errmsg(sqlDB->db)); } gseMutexUnlock(&dbMutex); // gseLog(L_INFO,"Open database"); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; if(localhost == NULL || user == NULL || password == NULL) { gseLog(L_ERROR,"localhost user password is NULL"); return -1; } char creatDbStr[64]={0}; char useDbStr[64]={0}; sprintf(creatDbStr, "create database %s", sqlName); sprintf(useDbStr, "use %s", sqlName); sqlDB->db= mysql_init(NULL); if (sqlDB->db== NULL) { gseLog(L_ERROR,"sqlOpen Error 1 %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); exit(1); } if (mysql_real_connect(sqlDB->db, localhost, user, password, NULL, 0, NULL, 0) == NULL) { gseLog(L_ERROR,"sqlOpen Error 2 %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); exit(1); } ret = mysql_query(sqlDB->db, creatDbStr); if (ret) { gseLog(L_ERROR,"sqlOpen Error 3 %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } ret = mysql_query(sqlDB->db, useDbStr); if (ret) { gseLog(L_ERROR,"sqlOpen Error 4 %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); exit(1); } #endif } else { return -2; } return ret; } int DBClose(dbClass *sqlDB) { if(NULL == sqlDB || NULL == sqlDB->db) { return -1; } int ret = 0; if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_close(sqlDB->db); gseMutexUnlock(&dbMutex); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; mysql_close(sqlDB->db); #endif } else { return -2; } // gseLog(L_INFO, "Close database"); return ret; } int DBCreate(dbClass *sqlDB, const char *tableName, char *creatValueStr) { if(sqlDB == NULL || tableName == NULL || creatValueStr == NULL || NULL == sqlDB->db || 0 == strlen(creatValueStr)) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; char createString[MAX_SQLSTR]={0}; if(strlen(creatValueStr) >= 1) creatValueStr[strlen(creatValueStr) - 1]='\0'; sprintf(createString, "create table %s(%s)", tableName,creatValueStr); //create table tb_cardId(cardID KEY, cardNum INT, endDate INT, password NVARCHAR(8)) memset(creatValueStr, 0, strlen(creatValueStr)); if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,createString,NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, create table fail: %s", ret, errmsg); } else gseLog(L_INFO, "create table %s success.", tableName); sqlite3_free(errmsg); gseMutexUnlock(&dbMutex); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, createString); if (ret) { gseLog(L_ERROR,"sqlCreate Error %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } #endif } else { return -2; } return ret; } int DBInsert(dbClass *sqlDB, const char *tableName, char *valuesString) { if(sqlDB == NULL || tableName == NULL || valuesString == NULL || NULL == sqlDB->db || 0 == strlen(valuesString)) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; char sqlInsetTable[MAX_SQLSTR]={0}; if(strlen(valuesString) >= 1) valuesString[strlen(valuesString)-1]='\0'; sprintf(sqlInsetTable, "insert into %s values(%s)",tableName,valuesString); //insert into tb_cardId values(1,124343223,20130101,'12345678'); memset(valuesString, 0, strlen(valuesString)); if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,sqlInsetTable,NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR, "%s",sqlInsetTable); gseLog(L_ERROR,"ret = %d, inset table fail: %s",ret,errmsg); } sqlite3_free(errmsg); gseMutexUnlock(&dbMutex); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, sqlInsetTable); if (ret) { gseLog(L_ERROR,"sqlInsert Error 4 %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } #endif } else { ret = -2; } if(1 == IsUpdateAll && 0 != ret) { rollBack(sqlDB); return ret; } return ret; } int DBUpdate(dbClass *sqlDB, const char *tableName, char *updateSetStr, char *updateWhereStr) { if(sqlDB == NULL || tableName == NULL || updateSetStr == NULL || updateWhereStr == NULL) { gseLog(L_ERROR,"*db is NULL"); return -1; } if(strlen(updateSetStr) >= 1) updateSetStr[strlen(updateSetStr)-1]='\0'; if(strlen(updateWhereStr) >= 3) updateWhereStr[strlen(updateWhereStr)-3]='\0'; char *errmsg = 0; int ret = 0; char sqlUpdateTable[MAX_SQLSTR]={0}; sprintf(sqlUpdateTable, "update %s set %s where %s", tableName, updateSetStr, updateWhereStr); //update tb_cardID set cardNum=1243423,password='323443' where cardID=1 and endDate=2013; memset(updateSetStr, 0, strlen(updateSetStr)); memset(updateWhereStr, 0, strlen(updateWhereStr)); if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,sqlUpdateTable,NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR, "%s",sqlUpdateTable); gseLog(L_ERROR,"ret = %d, update table fail: %s", ret, errmsg); } sqlite3_free(errmsg); gseMutexUnlock(&dbMutex); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, sqlUpdateTable); if (ret) { gseLog(L_ERROR,"sqlUpdate Error 4 %u: %s", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } #endif } else { ret = -2; } if(1 == IsUpdateAll && 0 != ret) { rollBack(sqlDB); return ret; } return ret; } int DBSearch(dbClass *sqlDB, const char *tableName, char *searchWhereStr, char (*returnValue)[SEARCH_MAXLEN]) { if(sqlDB == NULL || tableName == NULL || searchWhereStr == NULL) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; char sqlSearchTable[MAX_SQLSTR]={0}; int i; int nRow=0,nColumn=0; if(strlen(searchWhereStr) >= 3) searchWhereStr[strlen(searchWhereStr)-3]='\0'; sprintf(sqlSearchTable, "select * from %s where %s",tableName,searchWhereStr); //select * from tb_cardID where cardNum=323435; memset(searchWhereStr, 0, strlen(searchWhereStr)); if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; char **azResult; ret = sqlite3_get_table(sqlDB->db, sqlSearchTable, &azResult, &nRow, &nColumn,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR, "%s",sqlSearchTable); gseLog(L_ERROR,"ret = %d, search table fail: %s", ret, errmsg); } // gseLog(L_INFO,"row:%d column=%d",nRow, nColumn); for(i=nColumn;i<(nRow+1)*nColumn;i++) { // printf("azResult[%d] = %s\n", i, azResult[i]); if(azResult[i] != NULL && (*returnValue + SEARCH_MAXLEN*(i-nColumn)) != NULL) strcpy(*returnValue + SEARCH_MAXLEN*(i-nColumn), azResult[i]); } sqlite3_free_table(azResult); sqlite3_free(errmsg); gseMutexUnlock(&dbMutex); if(0 == nRow) return 1; else if(1 <= nRow) return 0; } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, sqlSearchTable); if (ret) { gseLog(L_ERROR,"sqlSearch Error 4 %u: %s\n", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } MYSQL_RES *result; MYSQL_ROW row; MYSQL_FIELD *field; int num_fields; result = mysql_store_result(sqlDB->db); num_fields = mysql_num_fields(result); while ((row = mysql_fetch_row(result))) { nRow++; for(i = 0; i < num_fields; i++) { if (i == 0) { while(field = mysql_fetch_field(result)) { printf("%s ", field->name); } printf("\n"); } printf("%s ", row[i] ? row[i] : "NULL"); } } printf("\n"); mysql_free_result(result); if(nRow == 0) return 0; else return nRow; #endif } return -2; } int DBDelete(dbClass *sqlDB, const char *tableName, char *searchWhereStr) { if(sqlDB == NULL || tableName == NULL || searchWhereStr == NULL) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; char sqlDeleteTable[MAX_SQLSTR]={0}; if(strlen(searchWhereStr) >= 3) { searchWhereStr[strlen(searchWhereStr)-3]='\0'; sprintf(sqlDeleteTable, "delete from %s where %s", tableName, searchWhereStr); memset(searchWhereStr, 0, strlen(searchWhereStr)); } else if(strlen(searchWhereStr) == 0) sprintf(sqlDeleteTable, "delete from %s", tableName); //delete from tb_cardID where cardID=1; // gseLog(L_DEBUG, "%s",sqlDeleteTable); if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,sqlDeleteTable,NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, delete table fail: %s", ret, errmsg); } sqlite3_free(errmsg); needVacuum = 1; #if 0 if (iDelCount++ > FREE_NUM) { iDelCount = 0; ret = sqlite3_exec(sqlDB->db,"vacuum",NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, vacuum fail: %s", ret, errmsg); } sqlite3_free(errmsg); } #endif gseMutexUnlock(&dbMutex); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, sqlDeleteTable); if (ret) { printf("sqlDelete Error %u: %s\n", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } #endif } else { ret = -2; } if(1 == IsUpdateAll && 0 != ret) { rollBack(sqlDB); return ret; } return ret; } int DBVacuum(dbClass *sqlDB) { if(sqlDB == NULL) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; if(sqlDB->type == SQL_SQLITE3 && 1 == needVacuum) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,"vacuum",NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, vacuum fail: %s", ret, errmsg); } else { needVacuum = 0; } sqlite3_free(errmsg); gseMutexUnlock(&dbMutex); } return ret; } int DBIndex(dbClass *sqlDB, const char *tableName, char *indexName, char *columnName) { if(sqlDB == NULL || tableName == NULL || indexName == NULL || columnName == NULL) { gseLog(L_ERROR,"SQLITE_Index NULL *p"); return -1; } int ret = 0; char *errmsg = 0; char sqlCreateIndex[MAX_SQLSTR]={0}; sprintf(sqlCreateIndex, "create index %s on %s(%s)", indexName, tableName, columnName); // gseLog(L_DEBUG, "%s",sqlCreateIndex); if(sqlDB->type == SQL_SQLITE3) { sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,sqlCreateIndex,NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, index table fail: %s", ret, errmsg); } sqlite3_free(errmsg); } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, sqlCreateIndex); if (ret) { printf("sqlIndex Error %u: %s\n", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } #endif } return ret; } int DBGetIdKey(dbClass *sqlDB, const char *tableName, const char *keyName, char (*returnValue)[ID_KEYLEN]) { if(sqlDB == NULL || tableName == NULL || keyName== NULL) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; char sqlSearchTable[MAX_SQLSTR]={0}; int i; int nRow=0,nColumn=0; sprintf(sqlSearchTable, "select %s from %s", keyName, tableName); if(sqlDB->type == SQL_SQLITE3) { gseMutexLock(&dbMutex); sqlDB->db = (sqlite3 *)sqlDB->db; char **azResult; ret = sqlite3_get_table(sqlDB->db, sqlSearchTable, &azResult, &nRow, &nColumn,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR, "%s",sqlSearchTable); gseLog(L_ERROR,"ret = %d, search table fail: %s", ret, errmsg); } // gseLog(L_INFO,"row:%d column=%d",nRow, nColumn); for(i=nColumn;i<(nRow+1)*nColumn;i++) { // printf("azResult[%d] = %s\n", i, azResult[i]); if(azResult[i] != NULL && (*returnValue + ID_KEYLEN*(i-nColumn)) != NULL) strcpy(*returnValue + ID_KEYLEN*(i-nColumn), azResult[i]); else break; } sqlite3_free_table(azResult); sqlite3_free(errmsg); gseMutexUnlock(&dbMutex); if(nRow == 0) return 0; else return nRow; } else if(sqlDB->type == SQL_MYSQL) { #ifdef MYSQL_DEFINE sqlDB->db = (MYSQL *)sqlDB->db; ret = mysql_query(sqlDB->db, sqlSearchTable); if (ret) { gseLog(L_ERROR,"sqlSearch Error 4 %u: %s\n", mysql_errno(sqlDB->db), mysql_error(sqlDB->db)); } MYSQL_RES *result; MYSQL_ROW row; MYSQL_FIELD *field; int num_fields; result = mysql_store_result(sqlDB->db); num_fields = mysql_num_fields(result); while ((row = mysql_fetch_row(result))) { nRow++; for(i = 0; i < num_fields; i++) { if (i == 0) { while(field = mysql_fetch_field(result)) { printf("%s ", field->name); } printf("\n"); } printf("%s ", row[i] ? row[i] : "NULL"); } } printf("\n"); mysql_free_result(result); if(nRow == 0) return 0; else return nRow; #endif } return -2; } int DBExecSql(dbClass *sqlDB, const char *sqlStr) { if(sqlDB == NULL || sqlStr == NULL) { gseLog(L_ERROR,"*db is NULL"); return -1; } char *errmsg = 0; int ret = 0; if(sqlDB->type == SQL_SQLITE3) { sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,sqlStr,NULL,NULL,&errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, exec sql(%s) fail: %s", ret, sqlStr, errmsg); } sqlite3_free(errmsg); } else if(sqlDB->type == SQL_MYSQL) { } return ret; } int dbAddColumn(char *createString, const char *keyName, const char *keyClass) { if(createString == NULL || keyName == NULL || keyClass == NULL) return -1; char tmpKey[128]; sprintf(tmpKey, "%s %s,", keyName, keyClass); strcat(createString, tmpKey); return 0; } int dbInsertColumn(char *insertString, char *value) { if(insertString == NULL || value == NULL) return -1; strcat(insertString,value); strcat(insertString,","); return 0; } int dbUpdateSet(char *updateSetStr, const char *setKey, char *setValue) { if(updateSetStr == NULL || setKey == NULL || setValue == NULL) return -1; char tmpStr[128]={0}; sprintf(tmpStr, " %s=%s,", setKey, setValue); strcat(updateSetStr, tmpStr); return 0; } int dbSearchWhere(char *searchWhereStr, const char *whereKey, char *whereValue) { if(searchWhereStr == NULL || whereKey == NULL || whereValue == NULL) return -1; char tmpStr[128]={0}; sprintf(tmpStr, " %s=%s and", whereKey, whereValue); strcat(searchWhereStr , tmpStr); return 0; } int setFlagIsUpdateAll(dbClass *sqlDB, int n) { int ret= 0; IsUpdateAll = n; if(-1 == IsUpdateAll) ret = rollBack(sqlDB); return ret; } int getFlagIsUpdateAll() { return IsUpdateAll; } int beginExclusive(dbClass *sqlDB) { int ret=0; char *errmsg = 0; sqlDB->db = (sqlite3 *)sqlDB->db; ret = sqlite3_exec(sqlDB->db,"BEGIN EXCLUSIVE", NULL,NULL, &errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, BEGIN EXCLUSIVE: %s", ret, errmsg); } sqlite3_free(errmsg); return ret; } int commitSQL(dbClass *sqlDB) { int ret=0; char *errmsg = 0; sqlDB->db = (sqlite3 *)sqlDB->db; ret=sqlite3_exec(sqlDB->db,"COMMIT", NULL,NULL, &errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, COMMIT: %s", ret, errmsg); } sqlite3_free(errmsg); return ret; } int rollBack(dbClass *sqlDB) { int ret=0; char *errmsg = 0; sqlDB->db = (sqlite3 *)sqlDB->db; ret=sqlite3_exec(sqlDB->db,"ROLLBACK", NULL,NULL, &errmsg); if(ret != SQLITE_OK) { gseLog(L_ERROR,"ret = %d, ROLLBACK: %s", ret, errmsg); } sqlite3_free(errmsg); return ret; } #ifdef MAIN_TEST void main() { char createValueStr[MAX_SQLSTR]={0}; char insertString[MAX_SQLSTR]={0}; char updateSetStr[MAX_SQLSTR]={0}; char searchWhereStr[MAX_SQLSTR]={0}; char *dbFileName="lkdb"; char *tableName="tb"; char *colList[]={"ID","names","sexsex"}; int ret=0; timeLog(); dbClass sqlDB; sqlDB.type = SQL_SQLITE3; DBOpen(&sqlDB, dbFileName, NULL, NULL, NULL); // sqlDB.type = SQL_MYSQL; // DBOpen(&sqlDB, dbFileName, "localhost", "root", "mima"); #if 1 dbAddColumn(createValueStr, colList[0], PRIMAY_KEY); dbAddColumn(createValueStr, colList[1], NVARCHAR_32); dbAddColumn(createValueStr, colList[2], NVARCHAR_32); DBCreate(&sqlDB, tableName, createValueStr); dbInsertColumn(insertString, "1"); dbInsertColumn(insertString, "'y_jg'"); dbInsertColumn(insertString, "'man'"); DBInsert(&sqlDB,tableName,insertString); dbInsertColumn(insertString, "2"); dbInsertColumn(insertString, "'lk'"); dbInsertColumn(insertString, "'man'"); DBInsert(&sqlDB,tableName,insertString); dbInsertColumn(insertString, "3"); dbInsertColumn(insertString, "'fqq'"); dbInsertColumn(insertString, "'woman'"); DBInsert(&sqlDB,tableName,insertString); dbInsertColumn(insertString, "4"); dbInsertColumn(insertString, "'xf'"); dbInsertColumn(insertString, "'man'"); DBInsert(&sqlDB,tableName,insertString); #endif dbUpdateSet(updateSetStr,"names", "'xxxx'"); dbSearchWhere(searchWhereStr,"id","3"); DBUpdate(&sqlDB,tableName,updateSetStr,searchWhereStr); DBClose(&sqlDB); timeLog(); } #endif</code>

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Keupayaan carian teks penuh InnoDB sangat kuat, yang dapat meningkatkan kecekapan pertanyaan pangkalan data dan keupayaan untuk memproses sejumlah besar data teks. 1) InnoDB melaksanakan carian teks penuh melalui pengindeksan terbalik, menyokong pertanyaan carian asas dan maju. 2) Gunakan perlawanan dan terhadap kata kunci untuk mencari, menyokong mod boolean dan carian frasa. 3) Kaedah pengoptimuman termasuk menggunakan teknologi segmentasi perkataan, membina semula indeks dan menyesuaikan saiz cache untuk meningkatkan prestasi dan ketepatan.

Ya, MySQL boleh dipasang pada Windows 7, dan walaupun Microsoft telah berhenti menyokong Windows 7, MySQL masih serasi dengannya. Walau bagaimanapun, perkara berikut harus diperhatikan semasa proses pemasangan: Muat turun pemasang MySQL untuk Windows. Pilih versi MySQL yang sesuai (komuniti atau perusahaan). Pilih direktori pemasangan yang sesuai dan set aksara semasa proses pemasangan. Tetapkan kata laluan pengguna root dan simpan dengan betul. Sambung ke pangkalan data untuk ujian. Perhatikan isu keserasian dan keselamatan pada Windows 7, dan disyorkan untuk menaik taraf ke sistem operasi yang disokong.

Perbezaan antara indeks clustered dan indeks bukan cluster adalah: 1. Klustered Index menyimpan baris data dalam struktur indeks, yang sesuai untuk pertanyaan oleh kunci dan julat utama. 2. Indeks Indeks yang tidak berkumpul indeks nilai utama dan penunjuk kepada baris data, dan sesuai untuk pertanyaan lajur utama bukan utama.

MySQL adalah sistem pengurusan pangkalan data sumber terbuka. 1) Buat Pangkalan Data dan Jadual: Gunakan perintah Createdatabase dan Createtable. 2) Operasi Asas: Masukkan, Kemas kini, Padam dan Pilih. 3) Operasi lanjutan: Sertai, subquery dan pemprosesan transaksi. 4) Kemahiran Debugging: Semak sintaks, jenis data dan keizinan. 5) Cadangan Pengoptimuman: Gunakan indeks, elakkan pilih* dan gunakan transaksi.

Dalam pangkalan data MySQL, hubungan antara pengguna dan pangkalan data ditakrifkan oleh kebenaran dan jadual. Pengguna mempunyai nama pengguna dan kata laluan untuk mengakses pangkalan data. Kebenaran diberikan melalui perintah geran, sementara jadual dibuat oleh perintah membuat jadual. Untuk mewujudkan hubungan antara pengguna dan pangkalan data, anda perlu membuat pangkalan data, membuat pengguna, dan kemudian memberikan kebenaran.

MySQL dan Mariadb boleh wujud bersama, tetapi perlu dikonfigurasikan dengan berhati -hati. Kuncinya adalah untuk memperuntukkan nombor port dan direktori data yang berbeza untuk setiap pangkalan data, dan menyesuaikan parameter seperti peruntukan memori dan saiz cache. Konfigurasi sambungan, konfigurasi aplikasi, dan perbezaan versi juga perlu dipertimbangkan dan perlu diuji dengan teliti dan dirancang untuk mengelakkan perangkap. Menjalankan dua pangkalan data secara serentak boleh menyebabkan masalah prestasi dalam situasi di mana sumber terhad.

Penyederhanaan Integrasi Data: AmazonRDSMYSQL dan Integrasi Data Integrasi Zero ETL Redshift adalah di tengah-tengah organisasi yang didorong oleh data. Proses tradisional ETL (ekstrak, menukar, beban) adalah kompleks dan memakan masa, terutamanya apabila mengintegrasikan pangkalan data (seperti Amazonrdsmysql) dengan gudang data (seperti redshift). Walau bagaimanapun, AWS menyediakan penyelesaian integrasi ETL sifar yang telah mengubah keadaan ini sepenuhnya, menyediakan penyelesaian yang mudah, hampir-sebenar untuk penghijrahan data dari RDSMYSQL ke redshift. Artikel ini akan menyelam ke integrasi RDSMYSQL Zero ETL dengan redshift, menjelaskan bagaimana ia berfungsi dan kelebihan yang dibawa kepada jurutera dan pemaju data.
