Creating DDML documents

DDML, a language based on XML (Extensible Markup Language), allows you to logically define the entities you want to add to the Precise schema, such as tables, views, indexes, foreign keys, and all other required components. It covers the common entities available in most popular DBMSs.

After you have defined all database entities in DDML, you must run the DDML creation script to physically create the entities in the database.

General DDML document format

The general format of a DDML document looks as follows:

Tag	Description
`<tables-definition>`	Root element of a DDML document. Its children are the main database entities: `<table-definition>`, `<ddl-definition>`, and `<view-definition>`. The `<tables-definition>` tag includes the product attribute, which indicates the product of this specific DDML definition.
`<table-definition>`	Includes the table-level attributes. Its children are the `<column-definition>`, `<index-definition>`, and `<foreign-key-definition>` tags. If a table is a statistics table, meaning means that the type attribute has the value STATISTICS, the `<summary-hour>`, `<summary-day>`, `<summary-week>`, and `<summary-month>` tags can be specified as children of the `<table-definition>` tag.
`<ddl-definition>`	Includes ddl-level attributes.
`<view-definition>`	Includes view-level attributes.

<tables-definition> tag

Root element of the DDML document.

Attribute Definition

product

Required. Holds the product short name (product shortcut) consisting if two characters that define the product.

In this case, three custom-defined products are available:

C1 For customer-defined 1
C2 For customer-defined 2
C3 For customer-defined 3

<table-definition> tag

Holds all of the information included in a single table.

Attribute	Definition
`name`	Required. Holds the table name.
`type`	Required. Specifies the table type and can hold one of the following values: Statistics. A PMDB table that holds information about certain database activity, summarized into hours or time slices. Events. A PMDB table that keeps a log of database incidents.
`pctfree`	Optional. Affects only Oracle and is developed as `PCTFREE pctfree`. Can have a value between 0 and 99. If the PMDB is a Microsoft SQL Server database, this attribute is transformed to `fill factor`.
`pctused`	Optional. Affects only Oracle and is developed as `PCTUSED pctused`. Can have a value between 0 and 99.
`initrans`	Optional. Affects only Oracle and is developed as `INITRANS initrans`. Can have a value between 1 and 255.
`maxtrans`	Optional. Affects only Oracle and is developed as `MAXTRANS maxtrans`. Can have a value between 1 and 255.
`oracle-storage-clause`	Optional. Affects only Oracle and is developed as `STORAGE(oracle-storage-clause)`. For example: `oracle-storage-clause="initial 1M next 1M minextents 1maxextents unlimited pctincrease 100"`
`oracle-additional-clause`	Optional. Added to support any other Oracle features that cannot be defined in an Oracle storage clause. For example: `NOLOGGING`
`filterable`	Required for statistics tables (`type=STATISTICS`). If one or more columns are not relevant or needed in the PMDB, set this attribute to `TRUE`. If a statistics table is filterable and some columns are specified as not needed in the load or summary control files, these columns are not loaded or summarized.

The <table-definition> tag can have the following children:

<column-definition>
<index-definition>
<foreign-key-definition>

Additional Child	Definition
`<summary-hour>`	Optional. Instructs to define an hour-level summary table for this table. Used for time slice statistics tables. The name of the summary table is specified by the name attribute (required). The summary table name should follow the naming conventions specified in Naming conventions.
`<summary-day>`	Optional. Instructs to define a day-level summary table for this table. The name of the summary table is specified by the name attribute (required). The summary table name should follow the naming conventions specified in Naming conventions.
`<summary-week>`	Optional. Instructs to define a week-level summary table for this table. The name of the summary table is specified by the name attribute (required). The summary table name should follow the naming conventions specified in Naming conventions.
`<summary-month>`	Optional. Instructs to define a month-level summary table for this table. The name of the summary table is specified by the name attribute (required). The summary table name should follow the naming conventions specified in Naming conventions.

<ddl-definition> tag

Holds DDL (Data Definition Language) and DML (Data Manipulation Language) statements that can be performed during installation or uninstallation, such as stored procedures.

Attribute	Definition
`statement`	Required. Defines the DDL statement.
`dbms`	Optional. the RDBMS type on which the DDL generates. Must be one of the following: `oracle` `mssql` `""` If left empty (""), the DDL is created on all relational database management systems (RDBMS).
`version`	Optional. The RDBMS version on which the DDL generates. Should have the format `8.1. ...` If left empty, the DDL is created on all RDBMS versions.
`event`	Optional. The RDBMS version on which the DDL generates. Must be one of the following: `INSTALL` Default. During the installation process only. `UNINSTALL` During the uninstallation process only. `PREINSTALL` Before the installation process. `PREUNINSTALL` Before the uninstallation process.

<view-definition> tag

Holds all the parameters required for a view definition.

Attribute	Definition
`name`	Required. Holds the view name. The name should follow the naming conventions specified in Naming conventions.
`type`	Required. Specifies the view type and can hold one of the following values: `STATISTICS` A PMDB view that holds information about certain database activity, summarized into hours or time slices. `INTERNAL` A PMDB view that keeps any other, non-statistical information.
`view-columns`	Required. Its value is in the view columns separated by blanks. The number of columns should be equal to the number selected in the `as-query` attribute.
`as-query`	Required. Specifies the select table that defines the view.
`check-option`	Optional. Default value is `FALSE`. If the value is `TRUE`, only modifications that are visible through the view are allowed, meaning that `INSERT` and `UPDATE` statements are valid only if the affected rows can be retrieved by the view afterward.

<column-definition> tag

Holds all the parameters of a column.

Attribute	Definition
`name`	Required. Holds the column name. The name should follow the naming conventions specified in Naming conventions.
`data-type`	Required. Holds the data type of a column: `BOOLEAN` Does not require `data-length` or `data-scale` attributes. These attributes should not be specified. Implementation on all DBMSs: `CHAR(1)` where `T` is the boolean `TRUE` value and `F` is `FALSE`. `CHAR` Requires `data-length` attribute. Implementation on all DBMSs: `CHAR(data-length)` `CLOB` Requires `data-length` attribute. Implementation: `TEXT` for Microsoft SQL Server `CLOB` for Oracle `DECIMAL` Requires `data-length` (used for precision) and `data-scale` attributes. Implementation: `NUMBER(data-length, data-scale)` for Microsoft SQL Server and IBM UDB Oracle `FLOAT` Requires `data-length` attribute. Implementation: `FLOAT(data-length)` for Microsoft SQL Server `NUMBER` without any parameters for Oracle `INTEGER` Requires `data-length` attribute. Implementation: `data-length` less than three: `TINYINT`; `data-length` two-to-four: `SMALLINT`; `data-length` more than four: `BIGINT` for Microsoft SQL Server `NUMBER(data-length)` for Oracle `TIMESTAMP` Does not require `data-length` or `data-scale` attributes. These attributes should not be specified. Implementation: `DATETIME` for Microsoft SQL Server `TIME` for Oracle `UNIQUE INTEGER` Does not require `data-length` or `data-scale` attributes. These attributes should not be specified. This is a data type for a unique integer whose values are generated automatically. Implementation: `IDENTITY` for Microsoft SQL Server `NUMBER(20,0)` for Oracle. In addition, a `SEQUENCE` and a TRIGGER BEFORE INSERT are created, which select the `NEXTVAL` of the `SEQUENCE` from `DUAL`. `VARCHAR` Requires the `data-length` attribute. Implementation: `VARCHAR(data-length)` for Microsoft SQL Server `VARCHAR2(data-length)` for Oracle `VARBINARY` Requires the `data-length` attribute. Implementation: `VARBINARY(data-length)` for Microsoft SQL Server `RAW(data-length)` for Oracle
`data-length`
`data-scale`
`null`
`default`
`type`

Content

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