C語言和Oracle數據庫都是廣泛使用的技術，在實際開發中，有時候需要將圖片保存到Oracle數據庫中。本文將介紹如何使用C語言和Oracle，將圖片保存到Oracle數據庫。

首先，在C語言中讀取圖片并將圖片轉換成二進制格式。

FILE *fp;
long lSize;
unsigned char *buffer;
fp = fopen ( "test.jpg" , "rb" );
if( !fp ) {
printf("Image not found");
exit(1);
}
fseek( fp , 0L , SEEK_END);
lSize = ftell( fp );
rewind( fp );
buffer = (unsigned char*)calloc( 1, lSize+1 );
if( !buffer ){
fclose(fp);
printf("bad calloc");
exit(1);
}
if( 1!=fread( buffer , lSize, 1 , fp) ){
fclose(fp);
free(buffer);
printf("Read error");
exit(1);
}

接下來，將圖片數據插入到Oracle表中。

OCIEnv* envhp = NULL;
OCIError *errhp = NULL;
OCIServer *srvhp = NULL;
OCISvcCtx *svchp = NULL;
OCISession *usrhp = NULL;
OCIStmt *stmthp = NULL;
OCIBind *bndhp1 = NULL, *bndhp2 = NULL;
// Initialize OCI environment.
if (OCIInitialize(OCI_DEFAULT, (dvoid *)0, (dvoid * (*)(dvoid *, size_t))0, (dvoid * (*)(dvoid *, dvoid *, size_t))0,  (void (*)(dvoid *, dvoid *))0 ))
printf("OCIInitialize failed.");
if (OCIEnvInit(&envhp, OCI_DEFAULT, 0, NULL))
printf("OCIEnvInit failed.");
// Initialize OCI handles.
OCIHandleAlloc((dvoid *) envhp, (dvoid **) &errhp, OCI_HTYPE_ERROR,(size_t) 0, (dvoid **) NULL);
OCIHandleAlloc((dvoid *) envhp, (dvoid **) &srvhp, OCI_HTYPE_SERVER,(size_t) 0, (dvoid **) NULL);
OCIHandleAlloc((dvoid *) envhp, (dvoid **) &svchp, OCI_HTYPE_SVCCTX,(size_t) 0, (dvoid **) NULL);
OCIHandleAlloc((dvoid *) envhp, (dvoid **) &usrhp, OCI_HTYPE_SESSION, (size_t) 0, (dvoid **) NULL);
// Logon to server.
OCIServerAttach(srvhp, errhp, (text *)"localhost:1521/orcl", (sb4) strlen("localhost:1521/orcl"), OCI_DEFAULT);
OCIAttrSet((dvoid *) svchp, OCI_HTYPE_SVCCTX, (dvoid *)srvhp, (ub4) 0, OCI_ATTR_SERVER, errhp);
OCIAttrSet((dvoid *) usrhp, OCI_HTYPE_SESSION, "username", strlen("username"), OCI_ATTR_USERNAME, errhp);
OCIAttrSet((dvoid *) usrhp, OCI_HTYPE_SESSION, "password", strlen("password"), OCI_ATTR_PASSWORD, errhp);
OCISessionBegin(svchp, errhp, usrhp, OCI_CRED_RDBMS, OCI_DEFAULT);
// Prepare SQL statement.
ociresult = OCIStmtPrepare(stmthp, errhp, (text *)"INSERT INTO IMAGES(ID, IMAGE) VALUES(:id, :image)", strlen("INSERT INTO IMAGES(ID, IMAGE) VALUES(:id, :image)"), OCI_NTV_SYNTAX, OCI_DEFAULT);
// Bind the parameters.
OCIParamGet(stmthp, OCI_HTYPE_STMT, errhp, (dvoid **)&prmhp, (ub4) 1);
OCIBindByName(stmthp, &bndhp1, errhp, (text *)":id", strlen(":id"), (dvoid *)(&record.id), sizeof(record.id), SQLT_INT, (dvoid *)&id_ind, (ub2 *)0, (ub2 *)0, 0, (ub4 *)0, OCI_DEFAULT);
OCIBindByName(stmthp, &bndhp2, errhp, (text *)":image", strlen(":image"), bindbuffer, txtlen, SQLT_BIN, (dvoid *)&img_ind, (ub2 *)0, (ub2 *)0, 0, (ub4 *)0, OCI_DEFAULT);
// Execute the statement and check for errors.
OCIStmtExecute(svchp, stmthp, errhp, (ub4) 1, (ub4) 0, (OCISnapshot *) NULL, (OCISnapshot *) NULL, OCI_COMMIT_ON_SUCCESS);
// Cleanup.
OCISessionEnd(svchp, errhp, usrhp, OCI_DEFAULT);
OCIServerDetach(srvhp, errhp, OCI_DEFAULT);
OCIHandleFree((dvoid *)usrhp, OCI_HTYPE_SESSION);
OCIHandleFree((dvoid *)svchp, OCI_HTYPE_SVCCTX);
OCIHandleFree((dvoid *)srvhp, OCI_HTYPE_SERVER);
OCIHandleFree((dvoid *)envhp, OCI_HTYPE_ENV);

可以看到，使用OCIBindByName綁定參數，并使用OCIStmtExecute執行SQL語句。圖片數據存儲在bindbuffer中，id存儲在record.id中。

最后，我們來完整的看一下整個過程：

• 讀取圖片并將圖片轉換成二進制格式。
• 在Oracle數據庫中創建表，表的結構為ID(int)和IMAGE(BLOB)。
• 使用OCIBindByName進行參數綁定和執行SQL語句來將圖片數據插入到數據庫中。

總體來說，使用C語言和Oracle存儲圖片并不復雜，只需在讀取圖片并轉換格式后，將數據用Bind參數綁定后插入到數據庫中即可實現。