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Creating AXMLS (AdoDB XML Schema)

  • Namespace is schema :-) . The version=“0.2” attribute sets the version of the AXMLS DTD used by the XML schema.
<?xml version="1.0"?>
<schema version="0.2">
   ....
   ....
</schema>
Type Prefix Description
C Varchar, capped to 255 characters.
X Larger varchar, capped to 4000 characters (to be compatible with Oracle).
XL For Oracle, returns CLOB, otherwise the largest varchar size.
C2 Multibyte varchar
X2 Multibyte varchar (largest size)
B BLOB (binary large object)
D Date (some databases do not support this, and we return a datetime type)
T Datetime or Timestamp
L Integer field suitable for storing booleans (0 or 1)
I Integer (mapped to I4)
I1 1-byte integer
I2 2-byte integer
I4 4-byte integer
I8 8-byte integer
F Floating point number
N Numeric or decimal number
Keywords Description
AUTO For autoincrement number. Emulated with triggers if not available. Sets NOTNULL also.
AUTOINCREMENT Same as auto.
KEY Primary key field. Sets NOTNULL also. Compound keys are supported.
PRIMARY Same as KEY.
DEF Synonym for DEFAULT for lazy typists.
DEFAULT The default value. Character strings are auto-quoted unless the string begins and ends with spaces, eg ' SYSDATE '.
NOTNULL If field is not null.
DEFDATE Set default value to call function to get today's date.
DEFTIMESTAMP Set default to call function to get today's datetime.
NOQUOTE Prevents autoquoting of default string values.
CONSTRAINTS Additional constraints defined at the end of the field definition.
  • Here is an example
<?xml version="1.0"?>
<schema version="0.2">
 
  <table name="person_uuid">
    <desc>The central table on a person, with their associated names.</desc>
 
    <field name="p_uuid" type="I">
      <descr>A unique ID assigned to each person.</descr>
      <KEY/>
      <AUTOINCREMENT/>
    </field>
 
    <field name="full_name" type="C" size="100" />
    <field name="family_name" type="C" size="50" />
    <field name="l10n_name" type="C" size="100" />
    <field name="custom_name" type="C" size="50" />
 
    <index name="full_name">
      <descr>Put an unique index on the full name</descr>
      <col>full_name</col>
      <UNIQUE/>
    </index>
 
  </table>
 
</schema>

USING AXMLS

  • You need to include the sahana db handler and include the adodb xmlschema library
require_once( $global['approot']."/inc/db_handler.inc");
require_once( $global['approot']."/3rd/adodb/adodb-xmlschema.inc.php" );
  • Use the database connection to create a new adoSchema object.
$schema = new adoSchema( $global['db'] );
  • Call ParseSchema() to build SQL from the XML schema file. Then call the ExecuteSchema() to apply the resulting SQL to database.
$result = $schema->ExecuteSchema();

References


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