In a cached system, the base addresses of the last few referenced pages is maintained in registers called the TLB that aids in faster lookup. TLB contains those page-table entries that have been most recently used. Normally, each virtual memory reference causes 2 physical memory accesses-- one to fetch appropriate page-table entry, and one to fetch the desired data. Using TLB in-between, this is reduced to just one physical memory access in cases of TLB-hit.

mysql_fetch_array - Fetch a result row as an associative array and a numeric array.
mysql_fetch_object - Returns an object with properties that correspond to the fetched row and moves the internal data pointer ahead. Returns an object with properties that correspond to the fetched row, or FALSE if there are no more rows
mysql_fetch_row() - Fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.

mysql_fetch_array - Fetch a result row as an associative array, a numeric array, or both
mysql_fetch_assoc - Fetch a result row as an associative array

mysql_fetch_object - Fetch a result row as an object
mysql_fetch_row -- Get a result row as an enumerated array

MySQL fetch object will collect first single matching record where mysql_fetch_array will collect all matching records from the table in an array.

There are three types of buses. Address bus: This is used to carry the Address to the memory to fetch either Instruction or Data. Data bus : This is used to carry the Data from the memory. Control bus : This is used to carry the Control signals like RD/WR, Select etc.

Oracle Call Interface is a method of accesing database from a 3GL program. Uses-No precompiler is required,PL/SQL blocks are executed like other DML statements. The OCI library provides 1.functions to parse SQL statements 2.bind input variables 3.bind output variables 4.execute statements 5.fetch the results