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>

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics



Full table scanning may be faster in MySQL than using indexes. Specific cases include: 1) the data volume is small; 2) when the query returns a large amount of data; 3) when the index column is not highly selective; 4) when the complex query. By analyzing query plans, optimizing indexes, avoiding over-index and regularly maintaining tables, you can make the best choices in practical applications.

InnoDB's full-text search capabilities are very powerful, which can significantly improve database query efficiency and ability to process large amounts of text data. 1) InnoDB implements full-text search through inverted indexing, supporting basic and advanced search queries. 2) Use MATCH and AGAINST keywords to search, support Boolean mode and phrase search. 3) Optimization methods include using word segmentation technology, periodic rebuilding of indexes and adjusting cache size to improve performance and accuracy.

Yes, MySQL can be installed on Windows 7, and although Microsoft has stopped supporting Windows 7, MySQL is still compatible with it. However, the following points should be noted during the installation process: Download the MySQL installer for Windows. Select the appropriate version of MySQL (community or enterprise). Select the appropriate installation directory and character set during the installation process. Set the root user password and keep it properly. Connect to the database for testing. Note the compatibility and security issues on Windows 7, and it is recommended to upgrade to a supported operating system.

The difference between clustered index and non-clustered index is: 1. Clustered index stores data rows in the index structure, which is suitable for querying by primary key and range. 2. The non-clustered index stores index key values and pointers to data rows, and is suitable for non-primary key column queries.

MySQL is an open source relational database management system. 1) Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2) Basic operations: INSERT, UPDATE, DELETE and SELECT. 3) Advanced operations: JOIN, subquery and transaction processing. 4) Debugging skills: Check syntax, data type and permissions. 5) Optimization suggestions: Use indexes, avoid SELECT* and use transactions.

In MySQL database, the relationship between the user and the database is defined by permissions and tables. The user has a username and password to access the database. Permissions are granted through the GRANT command, while the table is created by the CREATE TABLE command. To establish a relationship between a user and a database, you need to create a database, create a user, and then grant permissions.

MySQL supports four index types: B-Tree, Hash, Full-text, and Spatial. 1.B-Tree index is suitable for equal value search, range query and sorting. 2. Hash index is suitable for equal value searches, but does not support range query and sorting. 3. Full-text index is used for full-text search and is suitable for processing large amounts of text data. 4. Spatial index is used for geospatial data query and is suitable for GIS applications.

MySQL and MariaDB can coexist, but need to be configured with caution. The key is to allocate different port numbers and data directories to each database, and adjust parameters such as memory allocation and cache size. Connection pooling, application configuration, and version differences also need to be considered and need to be carefully tested and planned to avoid pitfalls. Running two databases simultaneously can cause performance problems in situations where resources are limited.
