common.php

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     * Obtain DBMS specific SQL code portion needed to declare an text type
     * field to be used in statements like CREATE TABLE.
     *
     * @param array $field  associative array with the name of the properties
     *      of the field being declared as array indexes. Currently, the types
     *      of supported field properties are as follows:
     *
     *      length
     *          Integer value that determines the maximum length of the text
     *          field. If this argument is missing the field should be
     *          declared to have the longest length allowed by the DBMS.
     *
     *      default
     *          Text value to be used as default for this field.
     *
     *      notnull
     *          Boolean flag that indicates whether this field is constrained
     *          to not be set to null.
     * @return string  DBMS specific SQL code portion that should be used to
     *      declare the specified field.
     * @access public
     */
    function getTypeDeclaration($field)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        switch ($field['type']) {
        case 'text':
            $length = !empty($field['length']) ? $field['length'] : $db->options['default_text_field_length'];
            $fixed = !empty($field['fixed']) ? $field['fixed'] : false;
            return $fixed ? ($length ? 'CHAR('.$length.')' : 'CHAR('.$db->options['default_text_field_length'].')')
                : ($length ? 'VARCHAR('.$length.')' : 'TEXT');
        case 'clob':
            return 'TEXT';
        case 'blob':
            return 'TEXT';
        case 'integer':
            return 'INT';
        case 'boolean':
            return 'INT';
        case 'date':
            return 'CHAR ('.strlen('YYYY-MM-DD').')';
        case 'time':
            return 'CHAR ('.strlen('HH:MM:SS').')';
        case 'timestamp':
            return 'CHAR ('.strlen('YYYY-MM-DD HH:MM:SS').')';
        case 'float':
            return 'TEXT';
        case 'decimal':
            return 'TEXT';
        }
        return '';
    }

    // }}}
    // {{{ _getDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to declare a generic type
     * field to be used in statements like CREATE TABLE.
     *
     * @param string $name   name the field to be declared.
     * @param array  $field  associative array with the name of the properties
     *      of the field being declared as array indexes. Currently, the types
     *      of supported field properties are as follows:
     *
     *      length
     *          Integer value that determines the maximum length of the text
     *          field. If this argument is missing the field should be
     *          declared to have the longest length allowed by the DBMS.
     *
     *      default
     *          Text value to be used as default for this field.
     *
     *      notnull
     *          Boolean flag that indicates whether this field is constrained
     *          to not be set to null.
     *      charset
     *          Text value with the default CHARACTER SET for this field.
     *      collation
     *          Text value with the default COLLATION for this field.
     * @return string  DBMS specific SQL code portion that should be used to
     *      declare the specified field, or a MDB2_Error on failure
     * @access protected
     */
    function _getDeclaration($name, $field)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $name = $db->quoteIdentifier($name, true);
        $declaration_options = $db->datatype->_getDeclarationOptions($field);
        if (PEAR::isError($declaration_options)) {
            return $declaration_options;
        }
        return $name.' '.$this->getTypeDeclaration($field).$declaration_options;
    }

    // }}}
    // {{{ _getDeclarationOptions()

    /**
     * Obtain DBMS specific SQL code portion needed to declare a generic type
     * field to be used in statement like CREATE TABLE, without the field name
     * and type values (ie. just the character set, default value, if the
     * field is permitted to be NULL or not, and the collation options).
     *
     * @param array  $field  associative array with the name of the properties
     *      of the field being declared as array indexes. Currently, the types
     *      of supported field properties are as follows:
     *
     *      default
     *          Text value to be used as default for this field.
     *      notnull
     *          Boolean flag that indicates whether this field is constrained
     *          to not be set to null.
     *      charset
     *          Text value with the default CHARACTER SET for this field.
     *      collation
     *          Text value with the default COLLATION for this field.
     * @return string  DBMS specific SQL code portion that should be used to
     *      declare the specified field's options.
     * @access protected
     */
    function _getDeclarationOptions($field)
    {
        $charset = empty($field['charset']) ? '' :
            ' '.$this->_getCharsetFieldDeclaration($field['charset']);

        $notnull = empty($field['notnull']) ? '' : ' NOT NULL';
        $default = '';
        if (array_key_exists('default', $field)) {
            if ($field['default'] === '') {
                $db =& $this->getDBInstance();
                if (PEAR::isError($db)) {
                    return $db;
                }
                $valid_default_values = $this->getValidTypes();
                $field['default'] = $valid_default_values[$field['type']];
                if ($field['default'] === ''&& ($db->options['portability'] & MDB2_PORTABILITY_EMPTY_TO_NULL)) {
                    $field['default'] = ' ';
                }
            }
            if (!is_null($field['default'])) {
                $default = ' DEFAULT ' . $this->quote($field['default'], $field['type']);
            }
        }

        $collation = empty($field['collation']) ? '' :
            ' '.$this->_getCollationFieldDeclaration($field['collation']);

        return $charset.$default.$notnull.$collation;
    }

    // }}}
    // {{{ _getCharsetFieldDeclaration()
    
    /**
     * Obtain DBMS specific SQL code portion needed to set the CHARACTER SET
     * of a field declaration to be used in statements like CREATE TABLE.
     *
     * @param string $charset   name of the charset
     * @return string  DBMS specific SQL code portion needed to set the CHARACTER SET
     *                 of a field declaration.
     */
    function _getCharsetFieldDeclaration($charset)
    {
        return '';
    }

    // }}}
    // {{{ _getCollationFieldDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to set the COLLATION
     * of a field declaration to be used in statements like CREATE TABLE.
     *
     * @param string $collation   name of the collation
     * @return string  DBMS specific SQL code portion needed to set the COLLATION
     *                 of a field declaration.
     */
    function _getCollationFieldDeclaration($collation)
    {
        return '';
    }

    // }}}
    // {{{ _getIntegerDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to declare an integer type
     * field to be used in statements like CREATE TABLE.
     *
     * @param string $name name the field to be declared.
     * @param array $field associative array with the name of the properties
     *       of the field being declared as array indexes. Currently, the types
     *       of supported field properties are as follows:
     *
     *       unsigned
     *           Boolean flag that indicates whether the field should be
     *           declared as unsigned integer if possible.
     *
     *       default
     *           Integer value to be used as default for this field.
     *
     *       notnull
     *           Boolean flag that indicates whether this field is constrained
     *           to not be set to null.
     * @return string DBMS specific SQL code portion that should be used to
     *       declare the specified field.
     * @access protected
     */
    function _getIntegerDeclaration($name, $field)
    {
        if (!empty($field['unsigned'])) {
            $db =& $this->getDBInstance();
            if (PEAR::isError($db)) {
                return $db;
            }

            $db->warnings[] = "unsigned integer field \"$name\" is being declared as signed integer";
        }
        return $this->_getDeclaration($name, $field);
    }

    // }}}
    // {{{ _getTextDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to declare an text type
     * field to be used in statements like CREATE TABLE.
     *
     * @param string $name name the field to be declared.
     * @param array $field associative array with the name of the properties
     *       of the field being declared as array indexes. Currently, the types
     *       of supported field properties are as follows:
     *
     *       length
     *           Integer value that determines the maximum length of the text
     *           field. If this argument is missing the field should be
     *           declared to have the longest length allowed by the DBMS.
     *
     *       default
     *           Text value to be used as default for this field.
     *
     *       notnull
     *           Boolean flag that indicates whether this field is constrained
     *           to not be set to null.
     * @return string DBMS specific SQL code portion that should be used to
     *       declare the specified field.
     * @access protected
     */
    function _getTextDeclaration($name, $field)
    {
        return $this->_getDeclaration($name, $field);
    }

    // }}}
    // {{{ _getCLOBDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to declare an character
     * large object type field to be used in statements like CREATE TABLE.
     *
     * @param string $name name the field to be declared.
     * @param array $field associative array with the name of the properties
     *        of the field being declared as array indexes. Currently, the types
     *        of supported field properties are as follows:
     *
     *        length
     *            Integer value that determines the maximum length of the large
     *            object field. If this argument is missing the field should be
     *            declared to have the longest length allowed by the DBMS.
     *
     *        notnull
     *            Boolean flag that indicates whether this field is constrained
     *            to not be set to null.
     * @return string DBMS specific SQL code portion that should be used to
     *        declare the specified field.
     * @access public
     */
    function _getCLOBDeclaration($name, $field)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $notnull = empty($field['notnull']) ? '' : ' NOT NULL';
        $name = $db->quoteIdentifier($name, true);
        return $name.' '.$this->getTypeDeclaration($field).$notnull;
    }

    // }}}
    // {{{ _getBLOBDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to declare an binary large
     * object type field to be used in statements like CREATE TABLE.
     *
     * @param string $name name the field to be declared.
     * @param array $field associative array with the name of the properties
     *        of the field being declared as array indexes. Currently, the types
     *        of supported field properties are as follows:
     *
     *        length
     *            Integer value that determines the maximum length of the large
     *            object field. If this argument is missing the field should be
     *            declared to have the longest length allowed by the DBMS.
     *
     *        notnull
     *            Boolean flag that indicates whether this field is constrained
     *            to not be set to null.
     * @return string DBMS specific SQL code portion that should be used to
     *        declare the specified field.
     * @access protected
     */
    function _getBLOBDeclaration($name, $field)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $notnull = empty($field['notnull']) ? '' : ' NOT NULL';
        $name = $db->quoteIdentifier($name, true);
        return $name.' '.$this->getTypeDeclaration($field).$notnull;
    }

    // }}}
    // {{{ _getBooleanDeclaration()

    /**
     * Obtain DBMS specific SQL code portion needed to declare a boolean type
     * field to be used in statements like CREATE TABLE.
     *
     * @param string $name name the field to be declared.
     * @param array $field associative array with the name of the properties
     *       of the field being declared as array indexes. Currently, the types
     *       of supported field properties are as follows:
     *
     *       default
     *           Boolean value to be used as default for this field.
     *
     *       notnullL
     *           Boolean flag that indicates whether this field is constrained
     *           to not be set to null.
     * @return string DBMS specific SQL code portion that should be used to
     *       declare the specified field.
     * @access protected
     */
    function _getBooleanDeclaration($name, $field)
    {
        return $this->_getDeclaration($name, $field);
    }

    // }}}
    // {{{ _getDateDeclaration()

    /**