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/lib/ddl/ -> mysql_sql_generator.php (source)

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Differences Between: [Versions 311 and 402] [Versions 311 and 403]

Mysql specific SQL code generator.

Copyright: 1999 onwards Martin Dougiamas http://dougiamas.com
License: http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
File Size: 643 lines (28 kb)
Included or required:0 times
Referenced: 0 times
Includes or requires: 0 files

Defines 1 class

mysql_sql_generator:: (15 methods):
  getResetSequenceSQL()
  guess_antolope_row_size()
  guess_antelope_row_size()
  getCreateTableSQL()
  getAddFieldSQL()
  getAlterFieldSQL()
  getCreateTempTableSQL()
  getDropTableSQL()
  getTypeSQL()
  getCreateDefaultSQL()
  getRenameFieldSQL()
  getDropDefaultSQL()
  getCommentSQL()
  isNameInUse()
  getReservedWords()


Class: mysql_sql_generator  - X-Ref

This class generate SQL code to be used against MySQL
It extends XMLDBgenerator so everything can be
overridden as needed to generate correct SQL.

getResetSequenceSQL($table)   X-Ref
Reset a sequence to the id field of a table.

param: xmldb_table|string $table name of table or the table object.
return: array of sql statements

guess_antolope_row_size(array $columns)   X-Ref
Calculate proximate row size when using InnoDB
tables in Antelope row format.

Note: the returned value is a bit higher to compensate for
errors and changes of column data types.


guess_antelope_row_size(array $columns)   X-Ref
Calculate proximate row size when using InnoDB tables in Antelope row format.

Note: the returned value is a bit higher to compensate for errors and changes of column data types.

param: xmldb_field[]|database_column_info[] $columns
return: int approximate row size in bytes

getCreateTableSQL($xmldb_table)   X-Ref
Given one correct xmldb_table, returns the SQL statements
to create it (inside one array).

param: xmldb_table $xmldb_table An xmldb_table instance.
return: array An array of SQL statements, starting with the table creation SQL followed

getAddFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause = NULL, $skip_default_clause = NULL, $skip_notnull_clause = NULL)   X-Ref
Given one xmldb_table and one xmldb_field, return the SQL statements needed to add the field to the table.

param: xmldb_table $xmldb_table The table related to $xmldb_field.
param: xmldb_field $xmldb_field The instance of xmldb_field to create the SQL from.
param: string $skip_type_clause The type clause on alter columns, NULL by default.
param: string $skip_default_clause The default clause on alter columns, NULL by default.
param: string $skip_notnull_clause The null/notnull clause on alter columns, NULL by default.
return: array The SQL statement for adding a field to the table.

getAlterFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause = NULL, $skip_default_clause = NULL, $skip_notnull_clause = NULL)   X-Ref
No description

getCreateTempTableSQL($xmldb_table)   X-Ref
Given one correct xmldb_table, returns the SQL statements
to create temporary table (inside one array).

param: xmldb_table $xmldb_table The xmldb_table object instance.
return: array of sql statements

getDropTableSQL($xmldb_table)   X-Ref
Given one correct xmldb_table, returns the SQL statements
to drop it (inside one array).

param: xmldb_table $xmldb_table The table to drop.
return: array SQL statement(s) for dropping the specified table.

getTypeSQL($xmldb_type, $xmldb_length=null, $xmldb_decimals=null)   X-Ref
Given one XMLDB Type, length and decimals, returns the DB proper SQL type.

param: int $xmldb_type The xmldb_type defined constant. XMLDB_TYPE_INTEGER and other XMLDB_TYPE_* constants.
param: int $xmldb_length The length of that data type.
param: int $xmldb_decimals The decimal places of precision of the data type.
return: string The DB defined data type.

getCreateDefaultSQL($xmldb_table, $xmldb_field)   X-Ref
Given one xmldb_table and one xmldb_field, return the SQL statements needed to add its default
(usually invoked from getModifyDefaultSQL()

param: xmldb_table $xmldb_table The xmldb_table object instance.
param: xmldb_field $xmldb_field The xmldb_field object instance.
return: array Array of SQL statements to create a field's default.

getRenameFieldSQL($xmldb_table, $xmldb_field, $newname)   X-Ref
Given one correct xmldb_field and the new name, returns the SQL statements
to rename it (inside one array).

param: xmldb_table $xmldb_table The table related to $xmldb_field.
param: xmldb_field $xmldb_field The instance of xmldb_field to get the renamed field from.
param: string $newname The new name to rename the field to.
return: array The SQL statements for renaming the field.

getDropDefaultSQL($xmldb_table, $xmldb_field)   X-Ref
Given one xmldb_table and one xmldb_field, return the SQL statements needed to drop its default
(usually invoked from getModifyDefaultSQL()

Note that this method may be dropped in future.

param: xmldb_table $xmldb_table The xmldb_table object instance.
param: xmldb_field $xmldb_field The xmldb_field object instance.
return: array Array of SQL statements to create a field's default.

getCommentSQL($xmldb_table)   X-Ref
Returns the code (array of statements) needed to add one comment to the table.

param: xmldb_table $xmldb_table The xmldb_table object instance.
return: array Array of SQL statements to add one comment to the table.

isNameInUse($object_name, $type, $table_name)   X-Ref
Given one object name and it's type (pk, uk, fk, ck, ix, uix, seq, trg).

(MySQL requires the whole xmldb_table object to be specified, so we add it always)

This is invoked from getNameForObject().
Only some DB have this implemented.

param: string $object_name The object's name to check for.
param: string $type The object's type (pk, uk, fk, ck, ix, uix, seq, trg).
param: string $table_name The table's name to check in
return: bool If such name is currently in use (true) or no (false)

getReservedWords()   X-Ref
Returns an array of reserved words (lowercase) for this DB

return: array An array of database specific reserved words