calculate age with mysql

you can use mysql to determine how many years old of your employee is. This is just compute the difference in the year part of the current date and the birth date, then subtract one if the current date occurs earlier in the calendar year than the birth date. The following query shows, for each employee, name, birth date, the current date, and the age in the years. In this example I use table employee which has fields : employee_id, employee_name, birthdate

SELECT employee_id, employee_name, birthdate, CURDATE(),
(YEAR(CURDATE())-YEAR(birthdate))
- (RIGHT(CURDATE(),5)<RIGHT(birthdate,5))
AS age
FROM employee

SELECT Syntax MySQL

SELECT
    [ALL | DISTINCT | DISTINCTROW ]
      [HIGH_PRIORITY]
      [STRAIGHT_JOIN]
      [SQL_SMALL_RESULT] [SQL_BIG_RESULT] [SQL_BUFFER_RESULT]
      [SQL_CACHE | SQL_NO_CACHE] [SQL_CALC_FOUND_ROWS]
    select_expr, ...
    [FROM table_references
    [WHERE where_condition]
    [GROUP BY {col_name | expr | position}
      [ASC | DESC], ... [WITH ROLLUP]]
    [HAVING where_condition]
    [ORDER BY {col_name | expr | position}
      [ASC | DESC], ...]
    [LIMIT {[offset,] row_count | row_count OFFSET offset}]
    [PROCEDURE procedure_name(argument_list)]
    [INTO OUTFILE 'file_name' export_options
      | INTO DUMPFILE 'file_name'
      | INTO var_name [, var_name]]
    [FOR UPDATE | LOCK IN SHARE MODE]]

SELECT is used to retrieve rows selected from one or more tables, and can include UNION statements and subqueries. See Section 12.2.7.3, “UNION Syntax”, and Section 12.2.8, “Subquery Syntax”.

The most commonly used clauses of SELECT statements are these:

*

Each select_expr indicates a column that you want to retrieve. There must be at least one select_expr.
*

table_references indicates the table or tables from which to retrieve rows. Its syntax is described in Section 12.2.7.1, “JOIN Syntax”.
*

The WHERE clause, if given, indicates the condition or conditions that rows must satisfy to be selected. where_condition is an expression that evaluates to true for each row to be selected. The statement selects all rows if there is no WHERE clause.

In the WHERE clause, you can use any of the functions and operators that MySQL supports, except for aggregate (summary) functions. See Chapter 11, Functions and Operators.

SELECT can also be used to retrieve rows computed without reference to any table.

For example:

mysql> SELECT 1 + 1;
-> 2

You are allowed to specify DUAL as a dummy table name in situations where no tables are referenced:

mysql> SELECT 1 + 1 FROM DUAL;
-> 2

DUAL is purely for the convenience of people who require that all SELECT statements should have FROM and possibly other clauses. MySQL may ignore the clauses. MySQL does not require FROM DUAL if no tables are referenced.

In general, clauses used must be given in exactly the order shown in the syntax description. For example, a HAVING clause must come after any GROUP BY clause and before any ORDER BY clause. The exception is that the INTO clause can appear either as shown in the syntax description or immediately preceding the FROM clause.

*

A select_expr can be given an alias using AS alias_name. The alias is used as the expression's column name and can be used in GROUP BY, ORDER BY, or HAVING clauses. For example:

SELECT CONCAT(last_name,', ',first_name) AS full_name
FROM mytable ORDER BY full_name;

The AS keyword is optional when aliasing a select_expr. The preceding example could have been written like this:

SELECT CONCAT(last_name,', ',first_name) full_name
FROM mytable ORDER BY full_name;

However, because the AS is optional, a subtle problem can occur if you forget the comma between two select_expr expressions: MySQL interprets the second as an alias name. For example, in the following statement, columnb is treated as an alias name:

SELECT columna columnb FROM mytable;

For this reason, it is good practice to be in the habit of using AS explicitly when specifying column aliases.
*

It is not allowable to use a column alias in a WHERE clause, because the column value might not yet be determined when the WHERE clause is executed. See Section B.1.5.4, “Problems with Column Aliases”.
*

The FROM table_references clause indicates the table or tables from which to retrieve rows. If you name more than one table, you are performing a join. For information on join syntax, see Section 12.2.7.1, “JOIN Syntax”. For each table specified, you can optionally specify an alias.

tbl_name [[AS] alias] [index_hint]

The use of index hints provides the optimizer with information about how to choose indexes during query processing. For a description of the syntax for specifying these hints, see Section 12.2.7.2, “Index Hint Syntax”.

You can use SET max_seeks_for_key=value as an alternative way to force MySQL to prefer key scans instead of table scans. See Section 5.2.3, “System Variables”.
*

You can refer to a table within the default database as tbl_name, or as db_name.tbl_name to specify a database explicitly. You can refer to a column as col_name, tbl_name.col_name, or db_name.tbl_name.col_name. You need not specify a tbl_name or db_name.tbl_name prefix for a column reference unless the reference would be ambiguous. See Section 8.2.1, “Identifier Qualifiers”, for examples of ambiguity that require the more explicit column reference forms.
*

A table reference can be aliased using tbl_name AS alias_name or tbl_name alias_name:

SELECT t1.name, t2.salary FROM employee AS t1, info AS t2
WHERE t1.name = t2.name;

SELECT t1.name, t2.salary FROM employee t1, info t2
WHERE t1.name = t2.name;

*

Columns selected for output can be referred to in ORDER BY and GROUP BY clauses using column names, column aliases, or column positions. Column positions are integers and begin with 1:

SELECT college, region, seed FROM tournament
ORDER BY region, seed;

SELECT college, region AS r, seed AS s FROM tournament
ORDER BY r, s;

SELECT college, region, seed FROM tournament
ORDER BY 2, 3;

To sort in reverse order, add the DESC (descending) keyword to the name of the column in the ORDER BY clause that you are sorting by. The default is ascending order; this can be specified explicitly using the ASC keyword.

If ORDER BY occurs within a subquery and also is applied in the outer query, the outermost ORDER BY takes precedence. For example, results for the following statement are sorted in descending order, not ascending order:

(SELECT ... ORDER BY a) ORDER BY a DESC;

Use of column positions is deprecated because the syntax has been removed from the SQL standard.
*

If you use GROUP BY, output rows are sorted according to the GROUP BY columns as if you had an ORDER BY for the same columns. To avoid the overhead of sorting that GROUP BY produces, add ORDER BY NULL:

SELECT a, COUNT(b) FROM test_table GROUP BY a ORDER BY NULL;

*

MySQL extends the GROUP BY clause so that you can also specify ASC and DESC after columns named in the clause:

SELECT a, COUNT(b) FROM test_table GROUP BY a DESC;

*

MySQL extends the use of GROUP BY to allow selecting fields that are not mentioned in the GROUP BY clause. If you are not getting the results that you expect from your query, please read the description of GROUP BY found in Section 11.11, “Functions and Modifiers for Use with GROUP BY Clauses”.
*

GROUP BY allows a WITH ROLLUP modifier. See Section 11.11.2, “GROUP BY Modifiers”.
*

The HAVING clause is applied nearly last, just before items are sent to the client, with no optimization. (LIMIT is applied after HAVING.)

A HAVING clause can refer to any column or alias named in a select_expr in the SELECT list or in outer subqueries, and to aggregate functions. However, the SQL standard requires that HAVING must reference only columns in the GROUP BY clause or columns used in aggregate functions. To accommodate both standard SQL and the MySQL-specific behavior of being able to refer columns in the SELECT list, MySQL 5.0.2 and up allows HAVING to refer to columns in the SELECT list, columns in the GROUP BY clause, columns in outer subqueries, and to aggregate functions.

For example, the following statement works in MySQL 5.0.2 but produces an error for earlier versions:

mysql> SELECT COUNT(*) FROM t GROUP BY col1 HAVING col1 = 2;

If the HAVING clause refers to a column that is ambiguous, a warning occurs. In the following statement, col2 is ambiguous because it is used as both an alias and a column name:

SELECT COUNT(col1) AS col2 FROM t GROUP BY col2 HAVING col2 = 2;

Preference is given to standard SQL behavior, so if a HAVING column name is used both in GROUP BY and as an aliased column in the output column list, preference is given to the column in the GROUP BY column.
*

Do not use HAVING for items that should be in the WHERE clause. For example, do not write the following:

SELECT col_name FROM tbl_name HAVING col_name > 0;

Write this instead:

SELECT col_name FROM tbl_name WHERE col_name > 0;

*

The HAVING clause can refer to aggregate functions, which the WHERE clause cannot:

SELECT user, MAX(salary) FROM users
GROUP BY user HAVING MAX(salary) > 10;

(This did not work in some older versions of MySQL.)
*

MySQL allows duplicate column names. That is, there can be more than one select_expr with the same name. This is an extension to standard SQL. Because MySQL also allows GROUP BY and HAVING to refer to select_expr values, this can result in an ambiguity:

SELECT 12 AS a, a FROM t GROUP BY a;

In that statement, both columns have the name a. To ensure that the correct column is used for grouping, use different names for each select_expr.
*

MySQL resolves unqualified column or alias references in ORDER BY clauses by searching in the select_expr values, then in the columns of the tables in the FROM clause. For GROUP BY or HAVING clauses, it searches the FROM clause before searching in the select_expr values. (For GROUP BY and HAVING, this differs from the pre-MySQL 5.0 behavior that used the same rules as for ORDER BY.)
*

The LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be non-negative integer constants (except when using prepared statements).

With two arguments, the first argument specifies the offset of the first row to return, and the second specifies the maximum number of rows to return. The offset of the initial row is 0 (not 1):

SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15

To retrieve all rows from a certain offset up to the end of the result set, you can use some large number for the second parameter. This statement retrieves all rows from the 96th row to the last:

SELECT * FROM tbl LIMIT 95,18446744073709551615;

With one argument, the value specifies the number of rows to return from the beginning of the result set:

SELECT * FROM tbl LIMIT 5; # Retrieve first 5 rows

In other words, LIMIT row_count is equivalent to LIMIT 0, row_count.

For prepared statements, you can use placeholders (supported as of MySQL version 5.0.7). The following statements will return one row from the tbl table:

SET @a=1;
PREPARE STMT FROM 'SELECT * FROM tbl LIMIT ?';
EXECUTE STMT USING @a;

The following statements will return the second to sixth row from the tbl table:

SET @skip=1; SET @numrows=5;
PREPARE STMT FROM 'SELECT * FROM tbl LIMIT ?, ?';
EXECUTE STMT USING @skip, @numrows;

For compatibility with PostgreSQL, MySQL also supports the LIMIT row_count OFFSET offset syntax.

If LIMIT occurs within a subquery and also is applied in the outer query, the outermost LIMIT takes precedence. For example, the following statement produces two rows, not one:

(SELECT ... LIMIT 1) LIMIT 2;

*

The SELECT ... INTO OUTFILE 'file_name' form of SELECT writes the selected rows to a file. The file is created on the server host, so you must have the FILE privilege to use this syntax. file_name cannot be an existing file, which among other things prevents files such as /etc/passwd and database tables from being destroyed. As of MySQL 5.0.19, the character_set_filesystem system variable controls the interpretation of the filename.

The SELECT ... INTO OUTFILE statement is intended primarily to let you very quickly dump a table to a text file on the server machine. If you want to create the resulting file on some client host other than the server host, you cannot use SELECT ... INTO OUTFILE. In that case, you should instead use a command such as mysql -e "SELECT ..." > file_name to generate the file on the client host.

SELECT ... INTO OUTFILE is the complement of LOAD DATA INFILE; the syntax for the export_options part of the statement consists of the same FIELDS and LINES clauses that are used with the LOAD DATA INFILE statement. See Section 12.2.5, “LOAD DATA INFILE Syntax”.

FIELDS ESCAPED BY controls how to write special characters. If the FIELDS ESCAPED BY character is not empty, it is used as a prefix that precedes following characters on output:
o

The FIELDS ESCAPED BY character
o

The FIELDS [OPTIONALLY] ENCLOSED BY character
o

The first character of the FIELDS TERMINATED BY and LINES TERMINATED BY values
o

ASCII NUL (the zero-valued byte; what is actually written following the escape character is ASCII “0”, not a zero-valued byte)

The FIELDS TERMINATED BY, ENCLOSED BY, ESCAPED BY, or LINES TERMINATED BY characters must be escaped so that you can read the file back in reliably. ASCII NUL is escaped to make it easier to view with some pagers.

The resulting file does not have to conform to SQL syntax, so nothing else need be escaped.

If the FIELDS ESCAPED BY character is empty, no characters are escaped and NULL is output as NULL, not \N. It is probably not a good idea to specify an empty escape character, particularly if field values in your data contain any of the characters in the list just given.

Here is an example that produces a file in the comma-separated values (CSV) format used by many programs:

SELECT a,b,a+b INTO OUTFILE '/tmp/result.txt'
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY '\n'
FROM test_table;

*

If you use INTO DUMPFILE instead of INTO OUTFILE, MySQL writes only one row into the file, without any column or line termination and without performing any escape processing. This is useful if you want to store a BLOB value in a file.
*

The INTO clause can name a list of one or more variables, which can be user-defined variables, or parameters or local variables within a stored function or procedure body. The selected values are assigned to the variables. The number of variables must match the number of columns.

Within a stored routine, the variables can be routine parameters or local variables. See Section 18.2.7.3, “SELECT ... INTO Statement”.
*
Note

Any file created by INTO OUTFILE or INTO DUMPFILE is writable by all users on the server host. The reason for this is that the MySQL server cannot create a file that is owned by anyone other than the user under whose account it is running. (You should never run mysqld as root for this and other reasons.) The file thus must be world-writable so that you can manipulate its contents.
*

The SELECT syntax description at the beginning this section shows the INTO clause near the end of the statement. It is also possible to use INTO OUTFILE or INTO DUMPFILE immediately preceding the FROM clause.
*

A PROCEDURE clause names a procedure that should process the data in the result set. For an example, see Section 26.3.1, “Procedure Analyse”.
*

If you use FOR UPDATE with a storage engine that uses page or row locks, rows examined by the query are write-locked until the end of the current transaction. Using LOCK IN SHARE MODE sets a shared lock that allows other transactions to read the examined rows but not to update or delete them. See Section 13.2.10.5, “SELECT ... FOR UPDATE and SELECT ... LOCK IN SHARE MODE Locking Reads”.

Following the SELECT keyword, you can use a number of options that affect the operation of the statement.

The ALL, DISTINCT, and DISTINCTROW options specify whether duplicate rows should be returned. If none of these options are given, the default is ALL (all matching rows are returned). DISTINCT and DISTINCTROW are synonyms and specify removal of duplicate rows from the result set.

HIGH_PRIORITY, STRAIGHT_JOIN, and options beginning with SQL_ are MySQL extensions to standard SQL.

*

HIGH_PRIORITY gives the SELECT higher priority than a statement that updates a table. You should use this only for queries that are very fast and must be done at once. A SELECT HIGH_PRIORITY query that is issued while the table is locked for reading runs even if there is an update statement waiting for the table to be free. This affects only storage engines that use only table-level locking (MyISAM, MEMORY, MERGE).

HIGH_PRIORITY cannot be used with SELECT statements that are part of a UNION.
*

STRAIGHT_JOIN forces the optimizer to join the tables in the order in which they are listed in the FROM clause. You can use this to speed up a query if the optimizer joins the tables in non-optimal order. See Section 6.2.1, “Optimizing Queries with EXPLAIN”. STRAIGHT_JOIN also can be used in the table_references list. See Section 12.2.7.1, “JOIN Syntax”.
*

SQL_BIG_RESULT can be used with GROUP BY or DISTINCT to tell the optimizer that the result set has many rows. In this case, MySQL directly uses disk-based temporary tables if needed, and prefers sorting to using a temporary table with a key on the GROUP BY elements.
*

SQL_BUFFER_RESULT forces the result to be put into a temporary table. This helps MySQL free the table locks early and helps in cases where it takes a long time to send the result set to the client.
*

SQL_SMALL_RESULT can be used with GROUP BY or DISTINCT to tell the optimizer that the result set is small. In this case, MySQL uses fast temporary tables to store the resulting table instead of using sorting. This should not normally be needed.
*

SQL_CALC_FOUND_ROWS tells MySQL to calculate how many rows there would be in the result set, disregarding any LIMIT clause. The number of rows can then be retrieved with SELECT FOUND_ROWS(). See Section 11.10.3, “Information Functions”.
*

SQL_CACHE tells MySQL to store the query result in the query cache if you are using a query_cache_type value of 2 or DEMAND. For a query that uses UNION or subqueries, this option effects any SELECT in the query. See Section 6.5.4, “The MySQL Query Cache”.
*

SQL_NO_CACHE tells MySQL not to store the query result in the query cache. See Section 6.5.4, “The MySQL Query Cache”. For a query that uses UNION or subqueries, this option effects any SELECT in the query.

Instalasi PHP, APACHE, MYSQL

bagi anda yang mau instalasi php, apache dan mysql satu-persatu. Bisa diwonload tutorialnya di sini. Tutorial berbentuk file swf....
1. Untuk instalasi di Windows, http://www.megaupload.com/?d=28V56YG8
2. Untuk instalasi di Linux, http://www.megaupload.com/?d=OGGHZH6S

Semoga tutorial di atas dapat membantu.....

Using ADOdb with PHP and Oracle: an advanced tutorial

1. Introduction

Oracle is the most popular commercial database used with PHP. There are many ways of accessing Oracle databases in PHP. These include:

* The oracle extension
* The oci8 extension
* PEAR DB library
* ADOdb library

The wide range of choices is confusing to someone just starting with Oracle and PHP. I will briefly summarize the differences, and show you the advantages of using ADOdb.

First we have the C extensions which provide low-level access to Oracle functionality. These C extensions are precompiled into PHP, or linked in dynamically when the web server starts up. Just in case you need it, here's a guide to installing Oracle and PHP on Linux.
Oracle extension Designed for Oracle 7 or earlier. This is obsolete.
Oci8 extension Despite it's name, which implies it is only for Oracle 8i, this is the standard method for accessing databases running Oracle 8i, 9i or 10g (and later).

Here is an example of using the oci8 extension to query the emp table of the scott schema with bind parameters:

$conn = OCILogon("scott","tiger", $tnsName);

$stmt = OCIParse($conn,"select * from emp where empno > :emp order by empno");
$emp = 7900;
OCIBindByName($stmt, ':emp', $emp);
$ok = OCIExecute($stmt);
while (OCIFetchInto($stmt,$arr)) {
print_r($arr);
echo "

---

";
}

This generates the following output:
Array ( [0] => 7902 [1] => FORD [2] => ANALYST [3] => 7566 [4] => 03/DEC/81 [5] => 3000 [7] => 20 ) Array ( [0] => 7934 [1] => MILLER [2] => CLERK [3] => 7782 [4] => 23/JAN/82 [5] => 1300 [7] => 10 )

We also have many higher level PHP libraries that allow you to simplify the above code. The most popular are PEAR DB and ADOdb. Here are some of the differences between these libraries:
Feature PEAR DB 1.6 ADOdb 4.52
General Style Simple, easy to use. Lacks Oracle specific functionality. Has multi-tier design. Simple high-level design for beginners, and also lower-level advanced Oracle functionality.
Support for Prepare Yes, but only on one statement, as the last prepare overwrites previous prepares. Yes (multiple simultaneous prepare's allowed)
Support for LOBs No Yes, using update semantics
Support for REF Cursors No Yes
Support for IN Parameters Yes Yes
Support for OUT Parameters No Yes
Schema creation using XML No Yes, including ability to define tablespaces and constraints
Provides database portability features No Yes, has some ability to abstract features that differ between databases such as dates, bind parameters, and data types.
Performance monitoring and tracing No Yes. SQL can be traced and linked to web page it was executed on. Explain plan support included.
Recordset caching for frequently used queries No Yes. Provides great speedups for SQL involving complex where, group-by and order-by clauses.
Popularity Yes, part of PEAR release Yes, many open source projects are using this software, including PostNuke, Xaraya, Mambo, Tiki Wiki.
Speed Medium speed. Very high speed. Fastest database abstraction library available for PHP. Benchmarks are available.
High Speed Extension available No Yes. You can install the optional ADOdb extension, which reimplements the most frequently used parts of ADOdb as fast C code. Note that the source code version of ADOdb runs just fine without this extension, and only makes use of the extension if detected.

PEAR DB is good enough for simple web apps. But if you need more power, you can see ADOdb offers more sophisticated functionality. The rest of this article will concentrate on using ADOdb with Oracle. You can find out more about connecting to Oracle later in this guide.
ADOdb Example

In ADOdb, the above oci8 example querying the emp table could be written as:

include "/path/to/adodb.inc.php";
$db = NewADOConnection("oci8");
$db->Connect($tnsName, "scott", "tiger");

$rs = $db->Execute("select * from emp where empno>:emp order by empno",
array('emp' => 7900));
while ($arr = $rs->FetchRow()) {
print_r($arr);
echo "

---

";
}

The Execute( ) function returns a recordset object, and you can retrieve the rows returned using $recordset->FetchRow( ).

If we ignore the initial connection preamble, we can see the ADOdb version is much easier and simpler:
Oci8 ADOdb

$stmt = OCIParse($conn,
"select * from emp where empno > :emp");
$emp = 7900;
OCIBindByName($stmt, ':emp', $emp);
$ok = OCIExecute($stmt);

while (OCIFetchInto($stmt,$arr)) {
print_r($arr);
echo "

---

";
}



$recordset = $db->Execute("select * from emp where empno>:emp",
array('emp' => 7900));

while ($arr = $recordset->FetchRow()) {
print_r($arr);
echo "

---

";
}


2. ADOdb Query Semantics

You can also query the database using the standard Microsoft ADO MoveNext( ) metaphor. The data array for the current row is stored in the fields property of the recordset object, $rs. MoveNext( ) offers the highest performance among all the techniques for iterating through a recordset:

$rs = $db->Execute("select * from emp where empno>:emp", array('emp' => 7900));
while (!$rs->EOF) {
print_r($rs->fields);
$rs->MoveNext();
}

And if you are interested in having the data returned in a 2-dimensional array, you can use:

$arr = $db->GetArray("select * from emp where empno>:emp", array('emp' => 7900));

Now to obtain only the first row as an array:

$arr = $db->GetRow("select * from emp where empno=:emp", array('emp' => 7900));

Or to retrieve only the first field of the first row:

$arr = $db->GetOne("select ename from emp where empno=:emp", array('emp' => 7900));

For easy pagination support, we provide the SelectLimit function. The following will perform a select query, limiting it to 100 rows, starting from row 201 (row 1 being the 1st row):

$offset = 200; $limitrows = 100;
$rs = $db->SelectLimit('select * from table', $limitrows, $offset);

The $offset parameter is optional.
Array Fetch Mode

When data is being returned in an array, you can choose the type of array the data is returned in.

1. Numeric indexes - use $connection->SetFetchMode(ADODB_FETCH_NUM).
2. Associative indexes - the keys of the array are the names of the fields (in upper-case). Use $connection->SetFetchMode(ADODB_FETCH_ASSOC).
3. Both numeric and associative indexes - use $connection->SetFetchMode(ADODB_FETCH_BOTH).

The default is ADODB_FETCH_BOTH for Oracle.
Caching

You can define a database cache directory using $ADODB_CACHE_DIR, and cache the results of frequently used queries that rarely change. This is particularly useful for SQL with complex where clauses and group-by's and order-by's. It is also good for relieving heavily-loaded database servers.

This example will cache the following select statement for 3600 seconds (1 hour):

$ADODB_CACHE_DIR = '/var/adodb/tmp';
$rs = $db->CacheExecute(3600, "select names from allcountries order by 1");

There are analogous CacheGetArray( ), CacheGetRow( ), CacheGetOne( ) and CacheSelectLimit( ) functions. The first parameter is the number of seconds to cache. You can also pass a bind array as a 3rd parameter (not shown above).

There is an alternative syntax for the caching functions. The first parameter is omitted, and you set the cacheSecs property of the connection object:

$ADODB_CACHE_DIR = '/var/adodb/tmp';
$connection->cacheSecs = 3600;
$rs = $connection->CacheExecute($sql, array('id' => 1));


3. Using Prepare( ) For Frequently Used Statements

Prepare( ) is for compiling frequently used SQL statement for reuse. For example, suppose we have a large array which needs to be inserted into an Oracle database. The following will result in a massive speedup in query execution (at least 20-40%), as the SQL statement only needs to be compiled once:

$stmt = $db->Prepare('insert into table (field1, field2) values (:f1, :f2)');
foreach ($arrayToInsert as $key => $value) {
$db->Execute($stmt, array('f1' => $key, 'f2' => $val);
}


4. Working With LOBs

Oracle treats data which is more than 4000 bytes in length specially. These are called Large Objects, or LOBs for short. Binary LOBs are BLOBs, and character LOBs are CLOBs. In most Oracle libraries, you need to do a lot of work to process LOBs, probably because Oracle designed it to work in systems with little memory. ADOdb tries to make things easy by assuming the LOB can fit into main memory.

ADOdb will transparently handle LOBs in select statements. The LOBs are automatically converted to PHP variables without any special coding.

For updating records with LOBs, the functions UpdateBlob( ) and UpdateClob( ) are provided. Here's a BLOB example. The parameters should be self-explanatory:

$ok = $db->Execute("insert into aTable (id, name, ablob)
values (aSequence.nextVal, 'Name', null)");
if (!$ok) return LogError($db->ErrorMsg());
# params: $tableName, $blobFieldName, $blobValue, $whereClause
$db->UpdateBlob('aTable', 'ablob', $blobValue, 'id=aSequence.currVal');

and the analogous CLOB example:

$ok = $db->Execute("insert into aTable (id, name, aclob)
values (aSequence.nextVal, 'Name', null)");
if (!$ok) return LogError($db->ErrorMsg());
$db->UpdateClob('aTable', 'aclob', $clobValue, 'id=aSequence.currVal');

Note that LogError( ) is a user-defined function, and not part of ADOdb.

Inserting LOBs is more complicated. Since ADOdb 4.55, we allow you to do this (assuming that the photo field is a BLOB, and we want to store $blob_data into this field, and the primary key is the id field):

$sql = "INSERT INTO photos ( ID, photo) ".
"VALUES ( :id, empty_blob() )".
" RETURNING photo INTO :xx";

$stmt = $db->PrepareSP($sql);
$db->InParameter($stmt, $id, 'id');
$blob = $db->InParameter($stmt, $blob_data, 'xx',-1, OCI_B_BLOB);
$db->StartTrans();
$ok = $db->Execute($stmt);
$db->CompleteTrans();

5. REF CURSORs

Oracle recordsets can be passed around as variables called REF Cursors. For example, in PL/SQL, we could define a function open_tab that returns a REF CURSOR in the first parameter:

TYPE TabType IS REF CURSOR RETURN TAB%ROWTYPE;

PROCEDURE open_tab (tabcursor IN OUT TabType,tablenames IN VARCHAR) IS
BEGIN
OPEN tabcursor FOR SELECT * FROM TAB WHERE tname LIKE tablenames;
END open_tab;

In ADOdb, we could access this REF Cursor using the ExecuteCursor() function. The following will find all table names that begin with 'A' in the current schema:

$rs = $db->ExecuteCursor("BEGIN open_tab(:refc,'A%'); END;",'refc');
while ($arr = $rs->FetchRow()) print_r($arr);

The first parameter is the PL/SQL statement, and the second parameter is the name of the REF Cursor.


6. In and Out Parameters

The following PL/SQL stored procedure requires an input variable, and returns a result into an output variable:

PROCEDURE data_out(input IN VARCHAR, output OUT VARCHAR) IS
BEGIN
output := 'I love '||input;
END;

The following ADOdb code allows you to call the stored procedure:

$stmt = $db->PrepareSP("BEGIN adodb.data_out(:a1, :a2); END;");
$input = 'Sophia Loren';
$db->InParameter($stmt,$input,'a1');
$db->OutParameter($stmt,$output,'a2');
$ok = $db->Execute($stmt);
if ($ok) echo ($output == 'I love Sophia Loren') ? 'OK' : 'Failed';

PrepareSP( ) is a special function that knows about bind parameters. The main limitation currently is that IN OUT parameters do not work.
Bind Parameters and REF CURSORs

We could also rewrite the REF CURSOR example to use InParameter (requires ADOdb 4.53 or later):

$stmt = $db->PrepareSP("BEGIN adodb.open_tab(:refc,:tabname); END;");
$input = 'A%';
$db->InParameter($stmt,$input,'tabname');
$rs = $db->ExecuteCursor($stmt,'refc');
while ($arr = $rs->FetchRow()) print_r($arr);

Bind Parameters and LOBs

You can also operate on LOBs. In this example, we have IN and OUT parameters using CLOBs.

$text = 'test test test';
$sql = "declare rs clob; begin :rs := lobinout(:sa0); end;";
$stmt = $conn -> PrepareSP($sql);
$conn -> InParameter($stmt,$text,'sa0', -1, OCI_B_CLOB); # -1 means variable length
$rs = '';
$conn -> OutParameter($stmt,$rs,'rs', -1, OCI_B_CLOB);
$conn -> Execute($stmt);
echo "return = ".$rs."
";

Similarly, you can use the constant OCI_B_BLOB to indicate that you are using BLOBs.
Reusing Bind Parameters with CURSOR_SHARING=FORCE

Many web programmers do not care to use bind parameters, and prefer to enter the SQL directly. So instead of:

$arr = $db->GetArray("select * from emp where empno>:emp", array('emp' => 7900));

They prefer entering the values inside the SQL:

$arr = $db->GetArray("select * from emp where empno>7900");

This reduces Oracle performance because Oracle will reuse compiled SQL which is identical to previously compiled SQL. The above example with the values inside the SQL is unlikely to be reused. As an optimization, from Oracle 8.1 onwards, you can set the following session parameter after you login:

ALTER SESSION SET CURSOR_SHARING=FORCE

This will force Oracle to convert all such variables (eg. the 7900 value) into constant bind parameters, improving SQL reuse.

More speedup tips.


7. Dates and Datetime in ADOdb

There are two things you need to know about dates in ADOdb.

First, to ensure cross-database compability, ADOdb assumes that dates are returned in ISO format (YYYY-MM-DD H24:MI:SS).

Secondly, since Oracle treats dates and datetime as the same data type, we decided not to display the time in the default date format. So on login, ADOdb will set the NLS_DATE_FORMAT to 'YYYY-MM-DD'. If you prefer to show the date and time by default, do this:

$db = NewADOConnection('oci8');
$db->NLS_DATE_FORMAT = 'RRRR-MM-DD HH24:MI:SS';
$db->Connect($tns, $user, $pwd);

Or execute:

$sql = "ALTER SESSION SET NLS_DATE_FORMAT = 'RRRR-MM-DD HH24:MI:SS'";
$db->Execute($sql);

If you are not concerned about date portability and do not use ADOdb's portability layer, you can use your preferred date format instead.

8. Database Portability Layer

ADOdb provides the following functions for portably generating SQL functions as strings to be merged into your SQL statements:
Function Description
DBDate($date) Pass in a UNIX timestamp or ISO date and it will convert it to a date string formatted for INSERT/UPDATE
DBTimeStamp($date) Pass in a UNIX timestamp or ISO date and it will convert it to a timestamp string formatted for INSERT/UPDATE
SQLDate($date, $fmt) Portably generate a date formatted using $fmt mask, for use in SELECT statements.
OffsetDate($date, $ndays) Portably generate a $date offset by $ndays.
Concat($s1, $s2, ...) Portably concatenate strings. Alternatively, for mssql use mssqlpo driver, which allows || operator.
IfNull($fld, $replaceNull) Returns a string that is the equivalent of MySQL IFNULL or Oracle NVL.
Param($name) Generates bind placeholders, using ? or named conventions as appropriate.
$db->sysDate Property that holds the SQL function that returns today's date
$db->sysTimeStamp Property that holds the SQL function that returns the current timestamp (date+time).
$db->concat_operator Property that holds the concatenation operator
$db->length Property that holds the name of the SQL strlen function.
$db->upperCase Property that holds the name of the SQL strtoupper function.
$db->random Property that holds the SQL to generate a random number between 0.00 and 1.00.
$db->substr Property that holds the name of the SQL substring function.

ADOdb also provides multiple oracle oci8 drivers for different scenarios:
Driver Name Description
oci805 Specifically for Oracle 8.0.5. This driver has a slower SelectLimit( ).
oci8 The default high performance driver. The keys of associative arrays returned in a recordset are upper-case.
oci8po The portable Oracle driver. Slightly slower than oci8. This driver uses ? instead of :bindvar for binding variables, which is the standard for other databases. Also the keys of associative arrays are in lower-case like other databases.

Here's an example of calling the oci8po driver. Note that the bind variables use question-mark:

$db = NewADOConnection('oci8po');
$db->Connect($tns, $user, $pwd);
$db->Execute("insert into atable (f1, f2) values (?,?)", array(12, 'abc'));


9. Connecting to Oracle

Before you can use ADOdb, you need to have the Oracle client installed and setup the oci8 extension. This extension comes pre-compiled for Windows (but you still need to enable it in the php.ini file). For information on compiling the oci8 extension for PHP and Apache on Unix, there is an excellent guide at oracle.com.
Should You Use Persistent Connections

One question that is frequently asked is should you use persistent connections to Oracle. Persistent connections allow PHP to recycle existing connections, reusing them after the previous web pages have completed. Non-persistent connections close automatically after the web page has completed. Persistent connections are faster because the cost of reconnecting is expensive, but there is additional resource overhead. As an alternative, Oracle allows you to pool and reuse server processes; this is called Shared Server (also known as MTS).

The author's benchmarks suggest that using non-persistent connections and the Shared Server configuration offer the best performance. If Shared Server is not an option, only then consider using persistent connections.
Connection Examples

Just in case you are having problems connecting to Oracle, here are some examples:

a. PHP and Oracle reside on the same machine, use default SID, with non-persistent connections:

$conn = NewADOConnection('oci8');
$conn->Connect(false, 'scott', 'tiger');

b. TNS Name defined in tnsnames.ora (or ONAMES or HOSTNAMES), eg. 'myTNS', using persistent connections:

$conn = NewADOConnection('oci8');
$conn->PConnect(false, 'scott', 'tiger', 'myTNS');

or

$conn->PConnect('myTNS', 'scott', 'tiger');

c. Host Address and SID

$conn->connectSID = true;
$conn->Connect('192.168.0.1', 'scott', 'tiger', 'SID');

d. Host Address and Service Name

$conn->Connect('192.168.0.1', 'scott', 'tiger', 'servicename');

e. Oracle connection string:

$cstr = "(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=$host)(PORT=$port))
(CONNECT_DATA=(SID=$sid)))";
$conn->Connect($cstr, 'scott', 'tiger');

f. ADOdb data source names (dsn):

$dsn = 'oci8://user:pwd@tnsname/?persist'; # persist is optional
$conn = ADONewConnection($dsn); # no need for Connect/PConnect

$dsn = 'oci8://user:pwd@host/sid';
$conn = ADONewConnection($dsn);

$dsn = 'oci8://user:pwd@/'; # oracle on local machine
$conn = ADONewConnection($dsn);

With ADOdb data source names, you don't have to call Connect( ) or PConnect( ).


10. Error Checking

The examples in this article are easy to read but a bit simplistic because we ignore error-handling. Execute( ) and Connect( ) will return false on error. So a more realistic way to call Connect( ) and Execute( ) is:

function InvokeErrorHandler()
{
global $db; ## assume global
MyLogFunction($db->ErrorNo(), $db->ErrorMsg());
}
if (!$db->Connect($tns, $usr, $pwd)) InvokeErrorHandler();

$rs = $db->Execute("select * from emp where empno>:emp order by empno",
array('emp' => 7900));
if (!$rs) return InvokeErrorHandler();
while ($arr = $rs->FetchRow()) {
print_r($arr);
echo "

---

";
}

You can retrieve the error message and error number of the last SQL statement executed from ErrorMsg( ) and ErrorNo( ). You can also define a custom error handler function. ADOdb also supports throwing exceptions in PHP5.


Handling Large Recordsets (added 27 May 2005)
The oci8 driver does not support counting the number of records returned in a SELECT statement, so the function RecordCount() is emulated when the global variable $ADODB_COUNTRECS is set to true, which is the default. We emulate this by buffering all the records. This can take up large amounts of memory for big recordsets. Set $ADODB_COUNTRECS to false for the best performance.

This variable is checked every time a query is executed, so you can selectively choose which recordsets to count.

PhpMyAdmin

Phpmyadmin adalah suatu aplikasi yang dibuat dengan bahasa pemrograman PHP yang ditujukan untuk pengelolaan basis data MySQL melalui Internet. Fungsi phpmyadmin sama dengan fungsi software lain seperti SQLYOG dan MySQLFront. Hanya saja PhpMyAdmin adalah free software. Sebelum mengikuti tutorial ini lebih lanjut, ada baiknya anda mendownload dulu phpmyadmin.

Cara Menggunakan Phpmyadmin

1. Pastikan Apache, PHP dan MySQL sudah terinstall di komputer Anda. Copy file phpMyAdmin-2.5.6.zip ke dalam folder di mana anda menyimpan file php (dalam Document Root)

2. Extract file tersebut sehingga akan terbentuk sebuah folder bernama phpMyAdmin-2.5.6

3. Bukalah web browser dan ketikkan http://localhost, lalu carilah folder tersebut.
Jika web browser anda menampilkan halaman sbb, maka anda harus mengatur / konfigurasi username dan password mysql di phpmyadmin terlebih dahulu.

4. Akan tetapi jika tampilannya sebagai berikut, berarti anda tidak perlu melakukan pengaturan / konfigurasi username dan password mysql di phpmyadmin

5. Jika tampilannya seperti pada gambar 3, maka anda harus melakukan konfigurasi username dan password mysqldi phpmyadmin. Caranya adalah buka folder phpMyAdmin-2.5.6 melalui windows explorer. Kemudian bukalah file config.inc.php (boleh menggunakan Dreamweaver maupun notepad).

6. Ubahlah beberapa settingan sbb :
di baris ke 69 : $cfg[’Servers’][$i][’host’] = ‘localhost’;
$cfg[’Servers’][$i][’host’] berisi host atau komputer tempat database mysql berada. Isi dengan localhost jika database mysql berada di komputer anda

Di baris ke-70 : $cfg[’Servers’][$i][’port’] = ‘’;
$cfg[’Servers’][$i][’port’] adalah port yang digunakan mysql. Kosongkan jika mysql anda menggunakan port standar (3306)

Di baris ke-83 : $cfg[’Servers’][$i][’user’] = ‘root’;
$cfg[’Servers’][$i][’user’] adalah user yang digunakan untuk koneksi ke mysql

Di baris ke-84 : $cfg[’Servers’][$i][’password’] = ‘’;
$cfg[’Servers’][$i][’password’] adalah password yang digunakan untuk koneksi ke mysql