日韩性视频-久久久蜜桃-www中文字幕-在线中文字幕av-亚洲欧美一区二区三区四区-撸久久-香蕉视频一区-久久无码精品丰满人妻-国产高潮av-激情福利社-日韩av网址大全-国产精品久久999-日本五十路在线-性欧美在线-久久99精品波多结衣一区-男女午夜免费视频-黑人极品ⅴideos精品欧美棵-人人妻人人澡人人爽精品欧美一区-日韩一区在线看-欧美a级在线免费观看

歡迎訪問 生活随笔!

生活随笔

當前位置: 首頁 > 运维知识 > 数据库 >内容正文

数据库

mysql fetch时间太长_sql_trace用法,fetch太多行需要运行很久怎么解决?

發布時間:2025/4/5 数据库 26 豆豆
生活随笔 收集整理的這篇文章主要介紹了 mysql fetch时间太长_sql_trace用法,fetch太多行需要运行很久怎么解决? 小編覺得挺不錯的,現在分享給大家,幫大家做個參考.

展開全部

#ifndef ___LIB_DB___

#define ___LIB_DB___

extern int DB_Open(char * dbcn, char * usr, char * pwd);

extern int DB_Exec(char * sql);

extern void * DB_Query(char *sql, const char *fmt, ...);

extern int DB_Next(void * hRecordset);

extern void DB_CleanQuery(void *hRecordset);

extern int DB_Close(void);

#endif

#ifdef WIN32

#include

#include

#include

#else

#include

#include

#define SQLHANDLE static MYSQL

#endif

#include

#include

#include

#include

SQLHANDLE hDBEnv, hDBC;

int DB_Open(char * dbcn, char * usr, char * pwd)

{

int r;

#ifdef WIN32

r = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &hDBEnv);

if(r) return 0;

r = SQLSetEnvAttr(hDBEnv,SQL_ATTR_ODBC_VERSION,

(void*)SQL_OV_ODBC3,0);

if(r) return 0;

r = SQLAllocHandle(SQL_HANDLE_DBC, hDBEnv, &hDBC);

if(r) return 0;

r = SQLConnect(hDBC,

(unsigned char *)dbcn, strlen(dbcn),

(unsigned char *)usr, strlen(usr),

(unsigned char *)pwd, strlen(pwd));

return r==SQL_SUCCESS |636f70793231313335323631343130323136353331333264643738| r==SQL_SUCCESS_WITH_INFO;

#else

mysql_init(&hDBC);

MYSQL * rx = mysql_real_connect(

&hDBC, dbcn, usr, pwd, NULL, 0, NULL, 0);

if(!rx) return 0;

return 1;

#endif

}//end DB_Open

int DB_Exec(char * sql)

{

#ifdef WIN32

SQLHANDLE hStatement = NULL;

SQLAllocHandle(SQL_HANDLE_STMT, hDBC, &hStatement);

SQLExecDirect(hStatement,(unsigned char *)sql, strlen(sql));

SQLCloseCursor(hStatement);

SQLFreeHandle(SQL_HANDLE_STMT, hStatement);

hStatement = NULL;

#else

mysql_real_query (&hDBC, sql, strlen(sql));

#endif

return 1;

}//end DB_Exec

int DB_Close(void)

{

#ifdef WIN32

SQLDisconnect(hDBC);

SQLFreeHandle(SQL_HANDLE_DBC, hDBC);

SQLFreeHandle(SQL_HANDLE_ENV, hDBEnv);

#else

mysql_close(&hDBC);

#endif

return 1;

}//DB_Close()

#ifndef WIN32

typedef struct tagMySQLRecordset {

MYSQL_RES * hRecord;

void * * row;

int * size;

int cols;

} MYSQLRecordset;

#endif

void DB_CleanQuery(void *hRecordset)

{

if(!hRecordset) return;

#ifdef WIN32

__try {

SQLCloseCursor(hRecordset);

SQLFreeHandle(SQL_HANDLE_STMT, hRecordset);

hRecordset = NULL;

}__finally{

return;

}//end try

#else

MYSQLRecordset * hRec = (MYSQLRecordset *) hRecordset;

mysql_free_result (hRec->hRecord);

free(hRec->row); hRec->row = NULL;

free(hRec->size); hRec->size = NULL;

free(hRec); hRec = NULL;

#endif

}//end DB_CleanQuery

int DB_Next(void * hRecordset)

{

int r=0; if(!hRecordset) return 0;

#ifdef WIN32

r = SQLFetch(hRecordset);

r = r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO;

if(!r) {

DB_CleanQuery(hRecordset);

}//end if

#else

MYSQLRecordset * hRec = (MYSQLRecordset *) hRecordset;

MYSQL_ROW row = mysql_fetch_row (hRec->hRecord);

if(row) {

for(int i=0; icols; i++) {

memcpy(hRec->row[i], row[i], hRec->size[i]);

}//next i

r = 1;

}else{

DB_CleanQuery(hRecordset);

r = 0;

}//end if

#endif

return r;

}//end DB_Next

int DB_params_count(const char * fmt)

{

int i=0, j=0;

while(fmt[i]) {

if(fmt[i]=='%') j++;

i++;

}//end while

return j;

}//end DB_params_count

void * DB_Query(char *sql, const char *fmt, ...)

{

int r=0;

int cols = DB_params_count(fmt);

if(cols<1) return NULL;

#ifdef WIN32

SQLHANDLE hStatement = NULL;

SQLAllocHandle(SQL_HANDLE_STMT, hDBC, &hStatement);

r = SQLExecDirect(hStatement,(unsigned char *)sql, strlen(sql));

r = r==SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO;

if(!r) {

return NULL;

}//end if

#else

r = mysql_real_query (&hDBC, sql, strlen(sql));

if(r) return NULL;

MYSQL_RES * rec = NULL;

rec = mysql_store_result (&hDBC);

if(!rec) return NULL;

MYSQLRecordset * hStatement

= (MYSQLRecordset *)malloc(sizeof(MYSQLRecordset));

if(!hStatement) return NULL;

memset(hStatement, 0, sizeof(MYSQLRecordset));

hStatement->hRecord = rec;

hStatement->cols = cols;

hStatement->row = (void **)malloc(cols * sizeof(void *));

memset(hStatement->row, 0, cols * sizeof(void *));

hStatement->size = (int *)malloc(cols * sizeof(int));

memset(hStatement->size, 0, cols * sizeof(int));

#endif

va_list ap; va_start(ap, fmt);

void * var; char buf[32];

int i=0,j=0,k=0,sz=0; char c=0;

int len = strlen(fmt); int bad=1;

#ifdef WIN32

int col=1;

#else

int col=0;

#endif

while(fmt[i]) {

c = fmt[i++];

if(c != '%') continue;

c = fmt[i++];

var = va_arg(ap, void *);

if(c == 'd') {

#ifdef WIN32

SQLBindCol(hStatement, col, SQL_C_SLONG, var, 4,NULL);

#else

hStatement->row[col] = var;

hStatement->size[col] = sizeof(long);

#endif

col++;

continue;

}//end if

if(c == 'f') {

#ifdef WIN32

SQLBindCol(hStatement, col, SQL_C_FLOAT, var, 4,NULL);

#else

hStatement->row[col] = var;

hStatement->size[col] = sizeof(float);

#endif

col++;

continue;

}//end if

memset(buf, 0, 32); bad=1;

for(j=i-1; j

c = fmt[j];

if(c>='0' && c<='9') buf[j-i+1]=c;

if(c=='s')

}//next j

if(bad) return NULL;

sscanf(buf, "%d", &sz);

#ifdef WIN32

SQLBindCol(hStatement, col, SQL_C_CHAR, var, sz, NULL);

#else

hStatement->row[col] = var;

hStatement->size[col] = sz;

#endif

col++;

i = k;

}//end while

va_end(ap);

return hStatement;

}//end DB_Rec

已贊過

已踩過<

你對這個回答的評價是?

評論

收起

總結

以上是生活随笔為你收集整理的mysql fetch时间太长_sql_trace用法,fetch太多行需要运行很久怎么解决?的全部內容,希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯,歡迎將生活随笔推薦給好友。