org.eigenbase.sql
Class SqlMerge

java.lang.Object
  org.eigenbase.sql.SqlNode
      org.eigenbase.sql.SqlCall
          org.eigenbase.sql.SqlMerge

All Implemented Interfaces:

Cloneable

public class SqlMerge
extends SqlCall

A SqlMerge is a node of a parse tree which represents a MERGE statement.

Field Summary

static int	ALIAS_OPERAND
static int	CONDITION_OPERAND
static int	INSERT_OPERAND
static int	OPERAND_COUNT
static int	SOURCE_SELECT_OPERAND
static int	SOURCE_TABLEREF_OPERAND
static int	TARGET_TABLE_OPERAND
static int	UPDATE_OPERAND

Fields inherited from class org.eigenbase.sql.SqlCall

operands

Fields inherited from class org.eigenbase.sql.SqlNode

emptyArray

Constructor Summary

SqlMerge(SqlSpecialOperator operator, SqlIdentifier targetTable, SqlNode condition, SqlNode source, SqlNode updateCall, SqlNode insertCall, SqlIdentifier alias, SqlParserPos pos)

Method Summary

SqlIdentifier	getAlias()
SqlNode	getCondition()
SqlInsert	getInsertCall()
SqlSelect	getSourceSelect() Gets the source SELECT expression for the data to be updated/inserted.
SqlNode	getSourceTableRef()
SqlIdentifier	getTargetTable()
SqlUpdate	getUpdateCall()
void	setSourceTableRef(SqlNode tableRef)
void	unparse(SqlWriter writer, int leftPrec, int rightPrec) Writes a SQL representation of this node to a writer.
void	validate(SqlValidator validator, SqlValidatorScope scope) Validates this call.

Methods inherited from class org.eigenbase.sql.SqlCall

accept, clone, equalsDeep, findValidOptions, getCallSignature, getFunctionQuantifier, getKind, getMonotonicity, getOperands, getOperator, isA, isCountStar, isExpanded, isName, setOperand, setOperator

Methods inherited from class org.eigenbase.sql.SqlNode

clone, cloneArray, equalDeep, getParserPosition, toSqlString, toSqlString, toString, validateExpr

Methods inherited from class java.lang.Object

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

Field Detail

TARGET_TABLE_OPERAND

public static final int TARGET_TABLE_OPERAND

See Also:

Constant Field Values

SOURCE_TABLEREF_OPERAND

public static final int SOURCE_TABLEREF_OPERAND

See Also:

Constant Field Values

CONDITION_OPERAND

public static final int CONDITION_OPERAND

See Also:

Constant Field Values

UPDATE_OPERAND

public static final int UPDATE_OPERAND

See Also:

Constant Field Values

INSERT_OPERAND

public static final int INSERT_OPERAND

See Also:

Constant Field Values

SOURCE_SELECT_OPERAND

public static final int SOURCE_SELECT_OPERAND

See Also:

Constant Field Values

ALIAS_OPERAND

public static final int ALIAS_OPERAND

See Also:

Constant Field Values

OPERAND_COUNT

public static final int OPERAND_COUNT

See Also:

Constant Field Values

Constructor Detail

SqlMerge

public SqlMerge(SqlSpecialOperator operator,
                SqlIdentifier targetTable,
                SqlNode condition,
                SqlNode source,
                SqlNode updateCall,
                SqlNode insertCall,
                SqlIdentifier alias,
                SqlParserPos pos)

Method Detail

getTargetTable

public SqlIdentifier getTargetTable()

Returns:

the identifier for the target table of the merge

getAlias

public SqlIdentifier getAlias()

Returns:

the alias for the target table of the merge

getSourceTableRef

public SqlNode getSourceTableRef()

Returns:

the source for the merge

setSourceTableRef

public void setSourceTableRef(SqlNode tableRef)

getUpdateCall

public SqlUpdate getUpdateCall()

Returns:

the update statement for the merge

getInsertCall

public SqlInsert getInsertCall()

Returns:

the insert statement for the merge

getCondition

public SqlNode getCondition()

Returns:

the condition expression to determine whether to update or insert

getSourceSelect

public SqlSelect getSourceSelect()

Gets the source SELECT expression for the data to be updated/inserted. Returns null before the statement has been expanded by SqlValidator.performUnconditionalRewrites.

Returns:

the source SELECT for the data to be updated

unparse

public void unparse(SqlWriter writer,
                    int leftPrec,
                    int rightPrec)

Description copied from class: SqlNode

Writes a SQL representation of this node to a writer.

The leftPrec and rightPrec parameters give us enough context to decide whether we need to enclose the expression in parentheses. For example, we need parentheses around "2 + 3" if preceded by "5 *". This is because the precedence of the "*" operator is greater than the precedence of the "+" operator.

The algorithm handles left- and right-associative operators by giving them slightly different left- and right-precedence.

If SqlWriter.isAlwaysUseParentheses() is true, we use parentheses even when they are not required by the precedence rules.

For the details of this algorithm, see SqlCall.unparse(org.eigenbase.sql.SqlWriter, int, int).

Overrides:

unparse in class SqlCall

Parameters:

writer - Target writer

leftPrec - The precedence of the SqlNode immediately preceding this node in a depth-first scan of the parse tree

rightPrec - The precedence of the SqlNode immediately

validate

public void validate(SqlValidator validator,
                     SqlValidatorScope scope)

Description copied from class: SqlCall

Validates this call.

The default implementation delegates the validation to the operator's SqlOperator.validateCall(org.eigenbase.sql.SqlCall, org.eigenbase.sql.validate.SqlValidator, org.eigenbase.sql.validate.SqlValidatorScope, org.eigenbase.sql.validate.SqlValidatorScope). Derived classes may override (as do, for example SqlSelect and SqlUpdate).

Overrides:

validate in class SqlCall

scope - Validator