de.ipcon.schema.generators

Class PostgreSQLTableMigrator

java.lang.Object

de.ipcon.schema.generators.PostgreSQLTableMigrator

public class PostgreSQLTableMigrator
extends java.lang.Object

Handler for Core Schema Definition logic.

This class is responsible for the structural table and column migration. It compares the in-memory MyTISM schema (SchemaI) against the physical database schema and computes the necessary DDL operations (CREATE TABLE, ALTER TABLE ADD/DROP/ALTER COLUMN) to synchronize them.

It enforces the Separation of Concerns principle by:

• Delegating all database read operations to the PostgreSQLCatalogInspector.
• Delegating PostgreSQL-specific table inheritance to the PostgreSQLInheritanceManager.
• Utilizing the PostgreSQLDDLBuilder to construct safe, SQL-injection-free queries.

Constructor Summary

Constructors

Constructor and Description
PostgreSQLTableMigrator(PostgreSQL pg, PostgreSQLMigrationContext ctx, PostgreSQLCatalogInspector inspector)

Method Summary

Modifier and Type	Method and Description
void	addSqlColumnsFromEntity(CBOEntityI entity, java.util.List<PostgreSQLColumn> toAdd) Adds the given new columns to the table for the entity via ALTER TABLE.
void	assureColHasNotNullConstraint(CBOEntityI entity, java.lang.String colName) Ensures that the specified column has a "NOT NULL" constraint.
void	checkConstraintNames(SchemaI schema) Checks for ill-named constraints in the database and drops them if they belong to an actively managed entity in the schema.
void	checkTableColumnsForSchema(SchemaI schema, java.lang.String remark, boolean noAlter, boolean nonDestructive) Checks that the tables for all entities exist and contain the set of columns matching their current attributes and creates them if required.
java.util.Map<java.lang.String,PostgreSQLColumn>	getColumnsForEntity(CBOEntityI entity) Gets the columns we *need* for the given entity according to the in-memory schema.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PostgreSQLTableMigrator

public PostgreSQLTableMigrator(PostgreSQL pg,
                               PostgreSQLMigrationContext ctx,
                               PostgreSQLCatalogInspector inspector)

Method Detail

checkConstraintNames

public void checkConstraintNames(SchemaI schema)

Checks for ill-named constraints in the database and drops them if they belong to an actively managed entity in the schema.

Parameters:

schema - The target schema definition.

checkTableColumnsForSchema

public void checkTableColumnsForSchema(SchemaI schema,
                                       java.lang.String remark,
                                       boolean noAlter,
                                       boolean nonDestructive)

Checks that the tables for all entities exist and contain the set of columns matching their current attributes and creates them if required.

Parameters:

schema - the SchemaI whose entities should be used

remark - informative remark only added to the log messages

noAlter - if true an already existing table for an entity will not be modified; only missing tables will be created

nonDestructive - if true no existing columns will be removed or altered, only missing columns will be added

assureColHasNotNullConstraint

public void assureColHasNotNullConstraint(CBOEntityI entity,
                                          java.lang.String colName)

Ensures that the specified column has a "NOT NULL" constraint.

This method checks if the column with the given name in the table for the specified entity has a "NOT NULL" constraint. If the constraint is not present, it is added to the column definition.

Parameters:

entity - The entity for the table containing the column.

colName - The name of the column to check.

addSqlColumnsFromEntity

public void addSqlColumnsFromEntity(CBOEntityI entity,
                                    java.util.List<PostgreSQLColumn> toAdd)

Adds the given new columns to the table for the entity via ALTER TABLE.

Parameters:

entity - The entity whose table needs to be altered.

toAdd - The list of missing columns to add.

getColumnsForEntity

public java.util.Map<java.lang.String,PostgreSQLColumn> getColumnsForEntity(CBOEntityI entity)

Gets the columns we *need* for the given entity according to the in-memory schema. Recursively includes columns required by base entities.

Parameters:

entity - The entity definition to process.

Returns:

A map of column names to their required PostgreSQL column definitions.