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PHP functions to operate MySQL_PHP tutorial
- WBOYOriginal
- 2016-07-20 10:59:47688browse
(1)mysql_connect(host, username, password);
Returns a connection number.
Note: The password of each mysql user can change according to the IP address of the machine where the user is located.
In addition, mSQL does not have a username mechanism, so msql_connect only requires a host parameter.
The host can be an IP address or a domain name.
(2)mysql_create_db (database name);
(3)mysql_select_db (database name, connection number);
Connect to a database.
(4)mysql_query (SQL statement, connection number);
If the SQL statement is select, a result number is returned. Otherwise, the returned value can be ignored.
If it fails, return false.
(5)mysql_fetch_array(result number);
Take out the next line and return an array. It can be accessed with numeric subscript (the first field is the subscript
0), you can also use string subscripts to access (that is, use each field name).
If the last row has been fetched, return false.
(6)mysql_fetch_field(result number,[field number]);
If there is no field number, remove the next field.
Returns a hash table with subscripts:
name,table,max_length,not_null,primary_key,unique_key,
multiple_key,numeric,blob,type,unsigned,zerofill
The meaning of each subscript should be relatively clear.
(7)mysql_num_rows(result number);mysql_num_fields(result number);
(8)mysql_free_result(result number);
(9)mysql_list_dbs();mysql_list_tables(database name);
(10)mysql_close(connection number);
(11)mysql_pconnect(host, username, password);
(12)mysql_select_db (database name, connection number);
Connect to a database.
Exactly similar to mysql_connect, but establishes a "permanent connection" that will never be established once established
Close, even if the mysql_close function is used or the program is executed, it will not be closed. The next time you try to build
When establishing a permanent connection, if the system finds that a permanent connection already exists, it will directly return the connection number and
Do not recreate.