Package liquibase.sqlgenerator.core

Class AbstractSqlGenerator<T extends SqlStatement>

java.lang.Object

liquibase.sqlgenerator.core.AbstractSqlGenerator<T>

Type Parameters:

T - an implementation of the SqlStatement specifying which logical SQL statement an instance of this template class is able to generate SQL for.

All Implemented Interfaces:

PrioritizedService, SqlGenerator<T>

Direct Known Subclasses:

AddAutoIncrementGenerator, AddColumnGenerator, AddDefaultValueGenerator, AddForeignKeyConstraintGenerator, AddPrimaryKeyGenerator, AddUniqueConstraintGenerator, AlterSequenceGenerator, BatchDmlExecutablePreparedStatementGenerator, ClearDatabaseChangeLogTableGenerator, CommentGenerator, CopyRowsGenerator, CreateDatabaseChangeLogLockTableGenerator, CreateDatabaseChangeLogTableGenerator, CreateDatabaseChangeLogTableGeneratorSybase, CreateIndexGenerator, CreateProcedureGenerator, CreateSequenceGenerator, CreateTableGenerator, CreateViewGenerator, CreateViewGeneratorInformix, DeleteGenerator, DropColumnGenerator, DropDefaultValueGenerator, DropForeignKeyConstraintGenerator, DropIndexGenerator, DropPrimaryKeyGenerator, DropProcedureGenerator, DropSequenceGenerator, DropTableGenerator, DropUniqueConstraintGenerator, DropViewGenerator, GetNextChangeSetSequenceValueGenerator, GetViewDefinitionGenerator, InitializeDatabaseChangeLogLockTableGenerator, InsertDataChangeGenerator, InsertGenerator, InsertOrUpdateGenerator, InsertSetGenerator, LockDatabaseChangeLogGenerator, MarkChangeSetRanGenerator, ModifyDataTypeGenerator, RawParameterizedSqlGenerator, RawSqlGenerator, ReindexGeneratorSQLite, RemoveChangeSetRanStatusGenerator, RenameColumnGenerator, RenameSequenceGenerator, RenameTableGenerator, RenameViewGenerator, ReorganizeTableGeneratorDB2, RuntimeGenerator, SelectFromDatabaseChangeLogGenerator, SelectFromDatabaseChangeLogLockGenerator, SetColumnRemarksGenerator, SetNullableGenerator, SetTableRemarksGenerator, SetViewRemarksGenerator, StoredProcedureGenerator, TableIsEmptyGenerator, TableRowCountGenerator, TagDatabaseGenerator, UnlockDatabaseChangeLogGenerator, UpdateChangeSetChecksumGenerator, UpdateDataChangeGenerator, UpdateGenerator

public abstract class AbstractSqlGenerator<T extends SqlStatement>
extends Object
implements SqlGenerator<T>

Generic template class for an SQL generator able to generate SQL for an object-form SqlStatement.

Field Summary

Fields inherited from interface liquibase.servicelocator.PrioritizedService

COMPARATOR

Fields inherited from interface liquibase.sqlgenerator.SqlGenerator

EMPTY_SQL, PRIORITY_DATABASE, PRIORITY_DEFAULT

Constructor Summary

Constructors

Constructor	Description
AbstractSqlGenerator()

Method Summary

Modifier and Type	Method	Description
boolean	generateRollbackStatementsIsVolatile(Database database)
boolean	generateStatementsIsVolatile(Database database)	Does this change require access to the database metadata? If true, the change cannot be used in an updateSql-style command.
int	getPriority()	Of all the SqlGenerators that "support" a given SqlStatement/Database, SqlGeneratorFactory will return the one with the highest priority.
boolean	looksLikeFunctionCall(String value, Database database)	Tries to find out if a given value (part a database-specific SQL statement) is just a simple literal (e.g.
boolean	supports(T statement, Database database)	Does this generator support the given statement/database combination? Do not validate the statement with this method, only return if it can support it.
Warnings	warn(T statementType, Database database, SqlGeneratorChain<T> sqlGeneratorChain)

Methods inherited from class java.lang.Object

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

Methods inherited from interface liquibase.sqlgenerator.SqlGenerator

generateSql, validate

Constructor Detail

AbstractSqlGenerator

public AbstractSqlGenerator()

Method Detail

getPriority

public int getPriority()

Description copied from interface: SqlGenerator

Of all the SqlGenerators that "support" a given SqlStatement/Database, SqlGeneratorFactory will return the one with the highest priority.

Specified by:

getPriority in interface PrioritizedService

Specified by:

getPriority in interface SqlGenerator<T extends SqlStatement>

generateStatementsIsVolatile

public boolean generateStatementsIsVolatile(Database database)

Description copied from interface: SqlGenerator

Does this change require access to the database metadata? If true, the change cannot be used in an updateSql-style command.

Specified by:

generateStatementsIsVolatile in interface SqlGenerator<T extends SqlStatement>

generateRollbackStatementsIsVolatile

public boolean generateRollbackStatementsIsVolatile(Database database)

Specified by:

generateRollbackStatementsIsVolatile in interface SqlGenerator<T extends SqlStatement>

supports

public boolean supports(T statement,
                        Database database)

Description copied from interface: SqlGenerator

Does this generator support the given statement/database combination? Do not validate the statement with this method, only return if it can support it.

Specified by:

supports in interface SqlGenerator<T extends SqlStatement>

warn

public Warnings warn(T statementType,
                     Database database,
                     SqlGeneratorChain<T> sqlGeneratorChain)

Specified by:

warn in interface SqlGenerator<T extends SqlStatement>

looksLikeFunctionCall

public boolean looksLikeFunctionCall(String value,
                                     Database database)

Tries to find out if a given value (part a database-specific SQL statement) is just a simple literal (e.g. 'Jones', 149.99 or false) or if it is a call to a function within the database (e.g. TO_DATE('28.12.2017', 'dd.mm.yyyy') in Oracle DB). This method is often used to determine if we need to quote literals which are Strings, e.g. if we determine "Dr. Jones" to be a literal, then we generate

INSERT INTO customers(last_name) VALUES('Dr. Jones')

but if the value is a function call, we may not quote it, e.g. for "TO_DATE('28.12.2017', 'dd.mm.yyyy')", we need to generate (note the absence of the apostrophes!):

INSERT INTO bookings(booking_date) VALUES (TO_DATE('28.12.2017', 'dd.mm.yyyy'))

Parameters:

value - The string to test

database - the database object to test against

Returns:

true if value looks like a function call, false if it looks like a literal.