MySQL using essays

Modify the structure within a table

Modify the column name and type command: ALTER TABLE tbuserinfo Change permissions (callout, this entry is the old field name) permissions (callout, this entry is the new field name) char (2);

The red callout 1 is the command, the Red Callout 2 is the result; for field deletion: 1, view table Tbuserinfo structure 2, delete the field Description command: ALTER table Tbuserinfo DROP Description;





MySQL DELETE statement: Delete from table name where condition; For example, delete from Tbuserinfo where id= 2;MySQL Query statement: SELECT * Column name from table name where condition; mysql fuzzy query: SELECT * FROM table name WHERE column name like "3%"; (indicates that all data with the first character of 3 in the column is queried)MySQL Modify statement: Update table name set column name = ' value ' where condition;MySQL INSERT statement: INSERT into table name values ' content ', ' content ';Linux C data insertion routines (self-write)

1MYSQL *Conn;2 time_t tm_val;3 structTM *GMT;4 Charsql[1024x768];5  6conn=Db_connect ();7Tm_val =Time (NULL);8GMT = LocalTime (&tm_val);9memset (SQL,0,1024x768);Tensprintf (SQL,"INSERT into Tbuserinfo (useraccount,pwd,permissions,createdatetime) VALUES ('%s ', '%s ', '%s ', '%d-%d-%d%d:%d:%d ') ", OneUsername,pwd,quanxian,gmt->tm_year +1900, Gmt->tm_mon +1, Gmt->tm_mday, Gmt->tm_hour, Gmt->tm_min, gmt->tm_sec); A  if(mysql_query (conn, sql)! =0) { -Do_log ("Insert failed!\n"); -  return 0; the  } -Db_disconnect (conn);

Linux c query get query content routines (self-write)

voidUser_list_find (Charresp_data[]) {MYSQL*Conn; Mysql_res*Res;intList_value;inttemp;Charsql[1024x768]; Charbuf[ -]; Charbuf1[4096]; Conn=Db_connect ();//mysql_res *rs;Mysql_row ROW; memset (SQL,0,1024x768); memset (BUF,0, -); memset (BUF1,0,4096); if(get_manager_quanxian[0] =='1') sprintf (SQL,"SELECT * from tbuserinfo WHERE permissions like \ "1%\""); Else if(get_manager_quanxian[0] =='2') sprintf (SQL,"SELECT * from tbuserinfo WHERE permissions like \ "2%\""); Else if(get_manager_quanxian[0]=='3') sprintf (SQL,"SELECT * from tbuserinfo WHERE permissions like \ "3%\""); mysql_query (conn, SQL);//Execute Query Statementres = MYSQL_STORE_RESULT (conn);//get query result setList_value=mysql_num_rows (RES);//get the number of rows found  for(temp=0; temp<list_value;temp++) {row=mysql_fetch_row (RES); sprintf (BUF,"%s,%s.", row[1],row[3]);   strcat (BUF1,BUF); } sprintf (Resp_data,"%d.", List_value); strcat (Resp_data, BUF1); Mysql_free_result (RES); //ReleaseDb_disconnect (conn);//Disconnect Connection}  

through the above two routines can be self-pondering update and delete;

MySQL using essays