net.hydromatic.quidem

Class Quidem

java.lang.Object

net.hydromatic.quidem.Quidem

public class Quidem
extends Object

Runs a SQL script.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Quidem.ConnectionFactory Creates a connection for a given name.
static interface	Quidem.NewConnectionFactory Deprecated.
static interface	Quidem.PropertyHandler Called whenever a property's value is changed.

Field Summary

Fields

Modifier and Type	Field and Description
static boolean	DEBUG
static Quidem.ConnectionFactory	EMPTY_CONNECTION_FACTORY The empty environment.
static com.google.common.base.Function<String,Object>	EMPTY_ENV The empty environment.
static Quidem.PropertyHandler	EMPTY_PROPERTY_HANDLER A property handler that does nothing.

Constructor Summary

Constructors

Constructor and Description
Quidem(Reader reader, Writer writer) Creates a Quidem interpreter with an empty environment and empty connection factory.
Quidem(Reader reader, Writer writer, com.google.common.base.Function<String,Object> env, Quidem.ConnectionFactory connectionFactory) Creates a Quidem interpreter.

Method Summary

Methods

Modifier and Type	Method and Description
void	execute() Executes the commands from the input, writing to the output, then closing both input and output.
boolean	isProbablyDeterministic(String sql) Returns whether a SQL query is likely to produce results always in the same order.
static void	main(String[] args) Entry point from the operating system command line.
void	setStackLimit(int stackLimit) Sets the maximum number of characters of an error stack to be printed.
Quidem	withConnectionFactory(Quidem.ConnectionFactory connectionFactory) Creates an instance that uses a given connection factory.
Quidem	withPropertyHandler(Quidem.PropertyHandler propertyHandler) Creates an instance that uses a given property handler.

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

public static final boolean DEBUG

EMPTY_ENV

public static final com.google.common.base.Function<String,Object> EMPTY_ENV

The empty environment. Returns null for all variables.

EMPTY_CONNECTION_FACTORY

public static final Quidem.ConnectionFactory EMPTY_CONNECTION_FACTORY

The empty environment. Returns null for all database names.

EMPTY_PROPERTY_HANDLER

public static final Quidem.PropertyHandler EMPTY_PROPERTY_HANDLER

A property handler that does nothing.

Constructor Detail

Quidem

public Quidem(Reader reader,
      Writer writer)

Creates a Quidem interpreter with an empty environment and empty connection factory.

Quidem

public Quidem(Reader reader,
      Writer writer,
      com.google.common.base.Function<String,Object> env,
      Quidem.ConnectionFactory connectionFactory)

Creates a Quidem interpreter.

Method Detail

withConnectionFactory

public Quidem withConnectionFactory(Quidem.ConnectionFactory connectionFactory)

Creates an instance that uses a given connection factory.

withPropertyHandler

public Quidem withPropertyHandler(Quidem.PropertyHandler propertyHandler)

Creates an instance that uses a given property handler.

main

public static void main(String[] args)

Entry point from the operating system command line.

Calls System.exit(int) with the following status codes:

• 0: success
• 1: invalid arguments
• 2: help

Parameters:

args - Command-line arguments

execute

public void execute()

Executes the commands from the input, writing to the output, then closing both input and output.

setStackLimit

public void setStackLimit(int stackLimit)

Sets the maximum number of characters of an error stack to be printed.

If negative, does not limit the stack size.

The default is DEFAULT_MAX_STACK_LENGTH.

Useful because it prevents diff from running out of memory if the error stack is very large. It is preferable to produce a result where you can see the first N characters of each stack trace than to produce no result at all.

Parameters:

stackLimit - Maximum number of characters to print of each stack trace

isProbablyDeterministic

public boolean isProbablyDeterministic(String sql)

Returns whether a SQL query is likely to produce results always in the same order.

If Quidem believes that the order is deterministic, it does not sort the rows before comparing them.

The result is just a guess. Quidem does not understand the finer points of SQL semantics.

Parameters:

sql - SQL query

Returns:

Whether the order is likely to be deterministic