Notes for learning PHP and MySQL interactive function tables

I have been studying PHP and MySQL recently. I feel that the interaction functions between PHP and MySQL are procedural. Of course, mysqli extensions, object-oriented functions, Java and C # are added, and PHP is written again, some do not adapt, and I feel that I have returned to the Age of C. I learned some functions today and recorded them so that I can refer to them when I forget them later.

Description	Letter count	Detailed description	Description
Establish Database Connection	Mysql_connect ()	Resource mysql_connect ([String hostname [: Port] [:/path/to/socket] [, string username] [, string Password]) Example: $ conn = @ mysql_connect ("localhost", "username", "password") or Dir ("cannot connect to MySQL Server ");	Close the connection that must be displayed when this connection is used
Establish Database Connection	Mysql_pconnect ()	Resource mysql_pconnect ([String hostname [: Port] [:/path/to/socket] [, string username] [, string Password]) Example: $ conn = @ mysql_pconnect ("localhost", "username", "password") or Dir ("cannot connect to MySQL Server ");	The connection function does not need to be displayed to close the connection. It is equivalent to using the connection pool.
Close database connection	Mysql_close ()	$ Conn = @ mysql_connect ("localhost", "username", "password") or die ("cannot connect to MySQL Server "); @ Mysql_select_db ("mydatabase") or die ("this database cannot be selected, or the database does not exist "); Echo "you have connected to mydatabase "; Mysql_close ();
Select Database	Mysql_select_db ()	Boolean mysql_select_db (string db_name [, resource link_id]) $ Conn = @ mysql_connect ("localhost", "username", "password") or die ("cannot connect to MySQL Server "); @ Mysql_select_db ("mydatabase") or die ("this database cannot be selected, or the database does not exist ");
Query MySQL	Mysql_query ()	Resource mysql_query (string query, [Resource link_id]) $ Linkid = @ mysql_connect ("localhost", "username", "password") or die ("cannot connect to MySQL Server "); @ Mysql_select_db ("mydatabase") or die ("this database cannot be selected, or the database does not exist "); $ Query = "select * From mytable "; $ Result = mysql_query ($ query ); Mysql_close ();	If the SQL query is successful, the resource identifier is returned. If the query fails, false is returned. If the update is successful, true is returned; otherwise, false is returned.
Query MySQL	Mysql_db_query ()	Resource mysql_db_query (string database, string Query [, resource link_id]) $ Linkid = @ mysql_connect ("localhost", "username", "password") or die ("cannot connect to mysqlserver "); $ Query = "select * From mytable "; $ Result = mysql_db_query ("mydatabase", $ query ); Mysql_close ();	This function is not recommended for code clarity.
Obtain and display data	Mysql_result ()	Mixed mysql_result (resource result_set, int row [, mixed field]) $ Query = "select ID, name from mytable order by name "; $ Result = mysql_query ($ query ); $ C_id = mysql_result ($ result, 0, "ID "); $ C_name = mysql_result ($ result, 0, "name ");	Simplest and least efficient Data Acquisition Function
Obtain and display data	Mysql_fetch_row ()	Array mysql_fetch_row (resource result_set) $ Query = "select ID, name from mytable order by name "; $ Result = mysql_query ($ query ); While (List ($ id, $ name) = mysql_fetch_row ($ result )){ Echo ("Name: $ name ($ id) <br/> "); }	The function retrieves the entire data row from result_set and places the value in an index array. Usually, the List () function is used.
Obtain and display data	Mysql_fetch_array ()	Array mysql_fetch_array (resource result_set [, int result_type]) $ Query = "select ID, name from mytable order by name "; $ Result = mysql_query ($ query ); While ($ ROW = mysql_fetch_array ($ result, mysql_assoc )){ $ Id = $ row ["ID"]; $ Name = $ row ["name"]; Echo "Name: $ name ($ id) <br/> "; }	Result_type has the following values: Mysql_assoc: field name indicates a key, and the field content is a value Mysql_num: numeric index array. The operation is the same as the mysql_fetch_ros () function. Mysql_both: it is returned as an associated array and a numerical index array. The default value of result_type.
Obtain and display data	Mysql_fetch_assoc ()	Array mysql_fetch_assoc (resource result_set) Call mysql_fetch_array (resource, mysql_assoc );
Obtain and display data	Mysql_fetch_object ()	Object mysql_fetch_object (resource result_set) $ Query = "select ID, name from mytable order by name "; While ($ ROW = mysql_fetch_object ($ result )){ $ Id = $ row-> ID; $ Name = $ row-> name; Echo "Name: $ name ($ id) <br/> "; }	The operation is the same as mysql_fetch_array ().
Selected record	Mysql_num_rows ()	Int mysql_num_rows (resource result_set) # Query = "select ID, name from mytable where ID> 65 "; $ Result = mysql_query ($ query ); Echo "has". mysql_num_rows ($ result). "The Record ID is greater than 65 ";	It is only useful when determining the number of records obtained by the SELECT query.
Affected records	Mysql_affected_rows ()	Int mysql_affected_rows ([Resource link_id]) $ Query = "Update mytable set name = 'cheneyfu' where ID> = 5 "; $ Result = mysql_query ($ query ); Echo "number of records whose ID is greater than or equal to 5:". mysql_affected_rows ();	This function obtains the number of rows affected by the insert, update, or delete update statements.
Obtain database list information	Mysql_list_dbs ()	Resource mysql_list_dbs ([Resource link_id]) Mysql_connect ("localhost", "username", "password "); $ DBS = mysql_list_dbs (); Echo "databases: <br/> "; While (List ($ dB) = mysql_fetch_rows ($ DBS )){ Echo "$ db <br/> "; }
Get Database Name	Mysql_db_name ()	String mysql_db_name (resource result_set, integer index)	This function is used to obtain the database name that is located in the specified index in the result_set returned by mysql_list_dbs ().
Obtain the database table list	Mysql_list_tables ()	Resource mysql_list_tables (string database [, resource link_id]) Mysql_connect ("localhost", "username", "password "); $ Tables = mysql_list_tables ("mydatabase "); While (List ($ table) = mysql_fetch_row ($ tables )){ Echo "$ table <br/> "; }	This function obtains the names of all tables in the database.
Get database table name	Mysql_tablename ()	String mysql_tablename (resource result_set, integer index) Mysql_connect ("localhost", "username", "password "); $ Tables = mysql_list_tables ("mydatabase "); $ COUNT =-1; While (++ $ count <mysql_numrows ($ tables )){ Echo mysql_tablename ($ tables, $ count). "<br/> "; }	This function obtains the name of the table in the specified index in result_set returned by mysql_list_tables ().
Obtain Field Information	Mysql_fetch_field ()	Object mysql_fetch_field (resource result [, int field_offset]) Mysql_connect ("localhost", "username", "password "); Mysql_select_db ("mydatabase "); $ Query = "select * From mytable "; $ Result = mysql_query ($ query ); $ Fields = mysql_num_fields ($ result ); For ($ COUNT = 0; $ count <$ fieds; $ count ++ ){ $ Field = mysql_fetch_field ($ result, $ count ); Echo "<p> $ field-> name $ field-> type ($ field-> max_length) </P> "; }	The returned object has 12 object attributes: Name: field name Table: The table where the field is located. Max_length: Maximum length of a field Not_null: if the field cannot be null, it is 1; otherwise, 0 Primary_key: if the field is a primary key, it is 1; otherwise, 0 Unique_key: if the field is a unique key, it is 1, otherwise 0 Multiple_key: if the field is not unique, it is 1; otherwise, 0 Numeric: if the field is a numerical value, it is 1; otherwise, it is 0. BLOB: if the field is blob, it is 1; otherwise, it is 0. Type: Data Type of the field Unsigned: if the field is unsigned, it is 1; otherwise, it is 0. Zerofill: if the field is "zero fill", it is 1; otherwise, it is 0.
Obtain the number of queried Fields	Mysql_num_fields ()	Integer mysql_num_fields (resource result_set) $ Query = "select ID, name from mytable order by name "; $ Result = mysql_query ($ query ); Echo "the number of fields in this query is:". mysql_num_fields ($ result). "<br/> ";	Returns the number of fields in result_set.
Obtains the field names of all fields in the specified table.	Mysql_list_fields ()	Resource mysql_list_fields (string database_name, string table_name [, resource link_id]) $ Fields = mysql_list_fields ("mydatabase", "mytable "); Echo "Number of mytable fields in the database mydatabase:". mysql_num_fields ($ fields). "<br/> ";
Obtains the specified field options.	Mysql_field_flags ()	String mysql_field_flags (resource result_set, integer field_offset)
Obtains the maximum length of a specified field.	Mysql_field_len ()	Integer mysql_field_len (resource result_set, integer field_offset) $ Query = "Select name from mytable "; $ Result = mysql_query ($ query ); $ ROW = mysql_fetch_row ($ result ); Echo mysql_field_len ($ result, 0). "<br/> ";	If mysql_field_len ($ reseult, 0) = 16777215 Then numer_format (mysql_field_len ($ result) is 16,777,215
Obtain the field name	Mysql_field_name ()	String mysql_field_name (resource result_set, int field_offset) $ Query = "select ID as pkid, name from mytable order by name "; $ Result = mysql_query ($ query ); $ ROW = mysql_fetch_row ($ result ); Echo mysql_field_name ($ result, 0); // result: pkid
Obtain the field type	Mysql_field_type ()	String mysql_field_type (resource result_set, int field_offset) $ Query = "select ID, name from mytable order by name "; $ Result = mysql_query ($ query ); $ ROW = mysql_fetch_row ($ result ); Echo mysql_field_type ($ result, 0); // result: int