@Override
final Field<T> getFunction0(Configuration configuration) {
SQLDialect family = configuration.family();
switch (family) {
case POSTGRES:
{
String field = method + "('" + getQualifiedName(configuration) + "')";
return field(field, getDataType());
}
case H2:
{
String field = method + "(" + getQualifiedName(configuration, true) + ")";
return field(field, getDataType());
}
case FIREBIRD:
case DERBY:
case HSQLDB:
{
if ("nextval".equals(method)) {
String field = "next value for " + getQualifiedName(configuration);
return field(field, getDataType());
} else if (family == FIREBIRD) {
return field("gen_id(" + getQualifiedName(configuration) + ", 0)", getDataType());
} else {
throw new SQLDialectNotSupportedException(
"The sequence's current value functionality is not supported for the "
+ family
+ " dialect.");
}
}
case CUBRID:
{
String field = getQualifiedName(configuration) + ".";
if ("nextval".equals(method)) {
field += "next_value";
} else {
field += "current_value";
}
return field(field, getDataType());
}
// Default is needed for hashCode() and toString()
default:
{
String field = getQualifiedName(configuration) + "." + method;
return field(field, getDataType());
}
}
}
@Override
final Field<Integer> getFunction0(Configuration configuration) {
switch (configuration.family()) {
case SQLITE:
switch (datePart) {
case YEAR:
return field("{strftime}('%Y', {0})", SQLDataType.INTEGER, field);
case MONTH:
return field("{strftime}('%m', {0})", SQLDataType.INTEGER, field);
case DAY:
return field("{strftime}('%d', {0})", SQLDataType.INTEGER, field);
case HOUR:
return field("{strftime}('%H', {0})", SQLDataType.INTEGER, field);
case MINUTE:
return field("{strftime}('%M', {0})", SQLDataType.INTEGER, field);
case SECOND:
return field("{strftime}('%S', {0})", SQLDataType.INTEGER, field);
default:
throw new SQLDialectNotSupportedException("DatePart not supported: " + datePart);
}
case DERBY:
switch (datePart) {
case YEAR:
return function("year", SQLDataType.INTEGER, field);
case MONTH:
return function("month", SQLDataType.INTEGER, field);
case DAY:
return function("day", SQLDataType.INTEGER, field);
case HOUR:
return function("hour", SQLDataType.INTEGER, field);
case MINUTE:
return function("minute", SQLDataType.INTEGER, field);
case SECOND:
return function("second", SQLDataType.INTEGER, field);
default:
throw new SQLDialectNotSupportedException("DatePart not supported: " + datePart);
}
case MARIADB:
case MYSQL:
case POSTGRES:
case HSQLDB:
case H2:
// A default implementation is necessary for hashCode() and toString()
default:
return field("{extract}({" + datePart.toSQL() + " from} {0})", SQLDataType.INTEGER, field);
}
}
private final QueryPart delegate(Configuration configuration) {
switch (configuration.family()) {
case CUBRID:
// There is a bug in CUBRID preventing reuse of "level" in the
// predicate http://jira.cubrid.org/browse/ENGINE-119
Field<Integer> level = from.add(level()).sub(one());
return table(
"({select} {0} {as} {1} {from} {2} {connect by} {level} <= {3})",
level, name("generate_series"), new Dual(), to.add(one()).sub(from));
case POSTGRES:
default:
return table("{generate_series}({0}, {1})", from, to);
}
}
@Override
final Field<T> getFunction0(Configuration configuration) {
switch (configuration.family()) {
case H2:
case HSQLDB:
return field("{nvl}({0}, {1})", getDataType(), arg1, arg2);
case DERBY:
case POSTGRES:
return field("{coalesce}({0}, {1})", getDataType(), arg1, arg2);
case MARIADB:
case MYSQL:
case SQLITE:
return field("{ifnull}({0}, {1})", getDataType(), arg1, arg2);
default:
return DSL.when(arg1.isNotNull(), arg1).otherwise(arg2);
}
}
@SuppressWarnings("unchecked")
@Override
final Field<T> getFunction0(Configuration configuration) {
// In any dialect, a single argument is always the least
if (getArguments().length == 1) {
return (Field<T>) getArguments()[0];
}
switch (configuration.family()) {
// This implementation has O(2^n) complexity. Better implementations
// are very welcome
case DERBY:
{
Field<T> first = (Field<T>) getArguments()[0];
Field<T> other = (Field<T>) getArguments()[1];
if (getArguments().length > 2) {
Field<?>[] remaining = new Field<?>[getArguments().length - 2];
System.arraycopy(getArguments(), 2, remaining, 0, remaining.length);
return DSL.when(first.lessThan(other), DSL.least(first, remaining))
.otherwise(DSL.least(other, remaining));
} else {
return DSL.when(first.lessThan(other), first).otherwise(other);
}
}
case FIREBIRD:
return function("minvalue", getDataType(), getArguments());
case SQLITE:
return function("min", getDataType(), getArguments());
default:
return function("least", getDataType(), getArguments());
}
}
@Override
final Field<String> getFunction0(Configuration configuration) {
switch (configuration.family()) {
// This beautiful expression was contributed by "Ludo", here:
// http://stackoverflow.com/questions/6576343/how-to-simulate-lpad-rpad-with-sqlite
case SQLITE:
{
return DSL.field(
"{0} || substr("
+ "replace("
+ "replace("
+ "substr("
+ "quote("
+ "zeroblob((({1} - length({0}) - 1 + length({2})) / length({2}) + 1) / 2)"
+ "), 3"
+ "), '\''', ''"
+ "), '0', {2}"
+ "), 1, ({1} - length({0}))"
+ ")",
String.class, field, length, character);
}
// According to the Firebird documentation, LPAD outcomes should be
// cast to truncate large results...
case FIREBIRD:
{
return field(
"cast(rpad({0}, {1}, {2}) as varchar(4000))",
SQLDataType.VARCHAR, field, length, character);
}
default:
{
return function("rpad", SQLDataType.VARCHAR, field, length, character);
}
}
}
@Override
public SQLDialect family() {
return delegate.family();
}