/*
* Copyright 2004-2013 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.lealone.dbobject.table;
import java.sql.Date;
import java.sql.ResultSetMetaData;
import java.sql.Timestamp;
import org.lealone.command.Parser;
import org.lealone.constant.Constants;
import org.lealone.constant.ErrorCode;
import org.lealone.dbobject.Schema;
import org.lealone.dbobject.Sequence;
import org.lealone.engine.Mode;
import org.lealone.engine.Session;
import org.lealone.expression.ConditionAndOr;
import org.lealone.expression.Expression;
import org.lealone.expression.ExpressionVisitor;
import org.lealone.expression.SequenceValue;
import org.lealone.expression.ValueExpression;
import org.lealone.message.DbException;
import org.lealone.result.Row;
import org.lealone.util.Bytes;
import org.lealone.util.MathUtils;
import org.lealone.util.StringUtils;
import org.lealone.value.DataType;
import org.lealone.value.Value;
import org.lealone.value.ValueDate;
import org.lealone.value.ValueInt;
import org.lealone.value.ValueLong;
import org.lealone.value.ValueNull;
import org.lealone.value.ValueString;
import org.lealone.value.ValueTime;
import org.lealone.value.ValueTimestamp;
import org.lealone.value.ValueUuid;
/**
* This class represents a column in a table.
*/
public class Column {
/**
* The name of the rowid pseudo column.
*/
public static final String ROWID = "_ROWID_";
/**
* The name of the rowkey pseudo column.
*/
public static final String ROWKEY = "_ROWKEY_";
/**
* This column is not nullable.
*/
public static final int NOT_NULLABLE = ResultSetMetaData.columnNoNulls;
/**
* This column is nullable.
*/
public static final int NULLABLE = ResultSetMetaData.columnNullable;
/**
* It is not know whether this column is nullable.
*/
public static final int NULLABLE_UNKNOWN = ResultSetMetaData.columnNullableUnknown;
private int type;
private long precision;
private int scale;
private int displaySize;
private Table table;
private String name;
private int columnId;
private boolean nullable = true;
private Expression defaultExpression;
private Expression checkConstraint;
private String checkConstraintSQL;
private String originalSQL;
private boolean autoIncrement;
private long start;
private long increment;
private boolean convertNullToDefault;
private Sequence sequence;
private boolean isComputed;
private TableFilter computeTableFilter;
private int selectivity;
private SingleColumnResolver resolver;
private String comment;
private boolean primaryKey;
private String columnFamilyName;
private byte[] nameAsBytes;
private byte[] columnFamilyNameeAsBytes;
private boolean isRowKeyColumn;
public void setRowKeyColumn(boolean isRowKeyColumn) {
this.isRowKeyColumn = isRowKeyColumn;
}
public boolean isRowKeyColumn() {
return isRowKeyColumn;
}
public boolean isTypeUnknown() {
return this.type == Value.UNKNOWN;
}
public String getColumnFamilyName() {
return columnFamilyName;
}
public void setColumnFamilyName(String columnFamilyName) {
this.columnFamilyName = columnFamilyName;
}
public byte[] getNameAsBytes() {
if (nameAsBytes == null)
nameAsBytes = Bytes.toBytes(name);
return nameAsBytes;
}
public byte[] getColumnFamilyNameAsBytes() {
if (columnFamilyNameeAsBytes == null)
columnFamilyNameeAsBytes = Bytes.toBytes(columnFamilyName);
return columnFamilyNameeAsBytes;
}
public void setType(int type) {
this.type = type;
DataType dt = DataType.getDataType(type);
precision = dt.defaultPrecision;
scale = dt.defaultScale;
displaySize = dt.defaultDisplaySize;
}
public Column(String name, int type) {
this(name, type, -1, -1, -1);
}
public Column(String name) {
int pos = name.indexOf('.');
if (pos != -1) {
columnFamilyName = name.substring(0, pos);
if (columnFamilyName != null && columnFamilyName.length() == 0)
columnFamilyName = null;
this.name = name.substring(pos + 1);
} else
this.name = name;
this.type = Value.UNKNOWN; //先设为Value.UNKNOWN，根据表达式的类型动态确定
}
public Column(String name, boolean isRowKeyColumn) {
this(name);
this.isRowKeyColumn = isRowKeyColumn;
}
public Column(String name, int type, long precision, int scale, int displaySize) {
if (name != null) {
int pos = name.indexOf('.');
if (pos != -1) {
columnFamilyName = name.substring(0, pos);
if (columnFamilyName != null && columnFamilyName.length() == 0)
columnFamilyName = null;
this.name = name.substring(pos + 1);
} else
this.name = name;
}
this.type = type;
if (precision == -1 && scale == -1 && displaySize == -1) {
DataType dt = DataType.getDataType(type);
precision = dt.defaultPrecision;
scale = dt.defaultScale;
displaySize = dt.defaultDisplaySize;
}
this.precision = precision;
this.scale = scale;
this.displaySize = displaySize;
}
public boolean equals(Object o) {
if (o == this) {
return true;
} else if (!(o instanceof Column)) {
return false;
}
Column other = (Column) o;
if (table == null || other.table == null || name == null || other.name == null) {
return false;
}
if (columnFamilyName != other.columnFamilyName)
return false;
if (columnFamilyName == null || other.columnFamilyName == null)
return false;
if (table != other.table) {
return false;
}
return name.equals(other.name) && columnFamilyName.equals(other.columnFamilyName);
}
public int hashCode() {
if (table == null || name == null) {
return 0;
}
if (columnFamilyName != null)
return table.getId() ^ columnFamilyName.hashCode() ^ name.hashCode();
else
return table.getId() ^ name.hashCode();
}
public Column getClone() {
Column newColumn = new Column(name, type, precision, scale, displaySize);
newColumn.copy(this);
return newColumn;
}
/**
* Convert a value to this column's type.
*
* @param v the value
* @return the value
*/
public Value convert(Value v) {
try {
return v.convertTo(type);
} catch (DbException e) {
if (e.getErrorCode() == ErrorCode.DATA_CONVERSION_ERROR_1) {
String target = (table == null ? "" : table.getName() + ": ") + getCreateSQL();
throw DbException.get(ErrorCode.DATA_CONVERSION_ERROR_1, v.getSQL() + " (" + target + ")");
}
throw e;
}
}
boolean getComputed() {
return isComputed;
}
/**
* Compute the value of this computed column.
*
* @param session the session
* @param row the row
* @return the value
*/
synchronized Value computeValue(Session session, Row row) {
computeTableFilter.setSession(session);
computeTableFilter.set(row);
return defaultExpression.getValue(session);
}
/**
* Set the default value in the form of a computed expression of other
* columns.
*
* @param expression the computed expression
*/
public void setComputedExpression(Expression expression) {
this.isComputed = true;
this.defaultExpression = expression;
}
/**
* Set the table and column id.
*
* @param table the table
* @param columnId the column index
*/
public void setTable(Table table, int columnId) {
this.table = table;
this.columnId = columnId;
}
public Table getTable() {
return table;
}
/**
* Set the default expression.
*
* @param session the session
* @param defaultExpression the default expression
*/
public void setDefaultExpression(Session session, Expression defaultExpression) {
// also to test that no column names are used
if (defaultExpression != null) {
defaultExpression = defaultExpression.optimize(session);
if (defaultExpression.isConstant()) {
defaultExpression = ValueExpression.get(defaultExpression.getValue(session));
}
}
this.defaultExpression = defaultExpression;
}
public int getColumnId() {
return columnId;
}
public String getSQL() {
if (table != null && !table.isStatic() && columnFamilyName != null)
return columnFamilyName + "." + Parser.quoteIdentifier(name);
else
return Parser.quoteIdentifier(name);
}
public String getName() {
return name;
}
public String getFullName() {
if (columnFamilyName != null)
return columnFamilyName + "." + name;
else
return name;
}
public int getType() {
return type;
}
public long getPrecision() {
return precision;
}
public void setPrecision(long p) {
precision = p;
}
public int getDisplaySize() {
return displaySize;
}
public int getScale() {
return scale;
}
public void setNullable(boolean b) {
nullable = b;
}
/**
* Validate the value, convert it if required, and update the sequence value
* if required. If the value is null, the default value (NULL if no default
* is set) is returned. Check constraints are validated as well.
*
* @param session the session
* @param value the value or null
* @return the new or converted value
*/
public Value validateConvertUpdateSequence(Session session, Value value) {
if (value == null) {
if (defaultExpression == null) {
value = ValueNull.INSTANCE;
} else {
synchronized (this) {
value = defaultExpression.getValue(session).convertTo(type);
}
if (primaryKey) {
session.setLastIdentity(value);
}
}
}
Mode mode = session.getDatabase().getMode();
if (value == ValueNull.INSTANCE) {
if (convertNullToDefault) {
synchronized (this) {
value = defaultExpression.getValue(session).convertTo(type);
}
}
if (value == ValueNull.INSTANCE && !nullable) {
if (mode.convertInsertNullToZero) {
DataType dt = DataType.getDataType(type);
if (dt.decimal) {
value = ValueInt.get(0).convertTo(type);
} else if (dt.type == Value.TIMESTAMP) {
value = ValueTimestamp.get(new Timestamp(session.getTransactionStart()));
} else if (dt.type == Value.TIME) {
value = ValueTime.fromNanos(0);
} else if (dt.type == Value.DATE) {
value = ValueDate.get(new Date(session.getTransactionStart()));
} else {
value = ValueString.get("").convertTo(type);
}
} else {
throw DbException.get(ErrorCode.NULL_NOT_ALLOWED, name);
}
}
}
if (checkConstraint != null) {
resolver.setValue(value);
Value v;
synchronized (this) {
v = checkConstraint.getValue(session);
}
// Both TRUE and NULL are ok
if (Boolean.FALSE.equals(v.getBoolean())) {
throw DbException.get(ErrorCode.CHECK_CONSTRAINT_VIOLATED_1, checkConstraint.getSQL());
}
}
value = value.convertScale(mode.convertOnlyToSmallerScale, scale);
if (precision > 0) {
if (!value.checkPrecision(precision)) {
String s = value.getTraceSQL();
if (s.length() > 127) {
s = s.substring(0, 128) + "...";
}
throw DbException.get(ErrorCode.VALUE_TOO_LONG_2, getCreateSQL(), s + " (" + value.getPrecision() + ")");
}
}
updateSequenceIfRequired(session, value);
return value;
}
private void updateSequenceIfRequired(Session session, Value value) {
if (sequence != null) {
long current = sequence.getCurrentValue();
long inc = sequence.getIncrement();
long now = value.getLong();
boolean update = false;
if (inc > 0 && now > current) {
update = true;
} else if (inc < 0 && now < current) {
update = true;
}
if (update) {
sequence.setStartValue(now + inc);
session.setLastIdentity(ValueLong.get(now));
sequence.flush(session);
}
}
}
/**
* Convert the auto-increment flag to a sequence that is linked with this
* table.
*
* @param session the session
* @param schema the schema where the sequence should be generated
* @param id the object id
* @param temporary true if the sequence is temporary and does not need to
* be stored
*/
public void convertAutoIncrementToSequence(Session session, Schema schema, int id, boolean temporary) {
if (!autoIncrement) {
DbException.throwInternalError();
}
if ("IDENTITY".equals(originalSQL)) {
originalSQL = "BIGINT";
} else if ("SERIAL".equals(originalSQL)) {
originalSQL = "INT";
}
String sequenceName;
while (true) {
ValueUuid uuid = ValueUuid.getNewRandom();
String s = uuid.getString();
s = s.replace('-', '_').toUpperCase();
sequenceName = "SYSTEM_SEQUENCE_" + s;
if (schema.findSequence(sequenceName) == null) {
break;
}
}
Sequence seq = session.createSequence(schema, id, sequenceName, true);
seq.setStartValue(start);
seq.setIncrement(increment);
if (!temporary) {
session.getDatabase().addSchemaObject(session, seq);
}
setAutoIncrement(false, 0, 0);
SequenceValue seqValue = new SequenceValue(seq);
setDefaultExpression(session, seqValue);
setSequence(seq);
}
/**
* Prepare all expressions of this column.
*
* @param session the session
*/
public void prepareExpression(Session session) {
if (defaultExpression != null) {
computeTableFilter = new TableFilter(session, table, null, false, null);
defaultExpression.mapColumns(computeTableFilter, 0);
defaultExpression = defaultExpression.optimize(session);
}
}
public String getCreateSQL() {
return getCreateSQL(false);
}
public String getCreateSQL(boolean isAlter) {
StringBuilder buff = new StringBuilder();
if (name != null) {
if (isAlter && table != null && !table.isStatic() && columnFamilyName != null)
buff.append(Parser.quoteIdentifier(columnFamilyName)).append('.').append(Parser.quoteIdentifier(name))
.append(' ');
else
buff.append(Parser.quoteIdentifier(name)).append(' ');
}
if (originalSQL != null) {
buff.append(originalSQL);
} else {
buff.append(DataType.getDataType(type).name);
switch (type) {
case Value.DECIMAL:
buff.append('(').append(precision).append(", ").append(scale).append(')');
break;
case Value.BYTES:
case Value.STRING:
case Value.STRING_IGNORECASE:
case Value.STRING_FIXED:
if (precision < Integer.MAX_VALUE) {
buff.append('(').append(precision).append(')');
}
break;
default:
}
}
if (defaultExpression != null) {
String sql = defaultExpression.getSQL();
if (sql != null) {
if (isComputed) {
buff.append(" AS ").append(sql);
} else if (defaultExpression != null) {
buff.append(" DEFAULT ").append(sql);
}
}
}
if (isRowKeyColumn) {
buff.append(" ROW KEY");
}
if (!nullable) {
buff.append(" NOT NULL");
}
if (convertNullToDefault) {
buff.append(" NULL_TO_DEFAULT");
}
if (sequence != null) {
buff.append(" SEQUENCE ").append(sequence.getSQL());
}
if (selectivity != 0) {
buff.append(" SELECTIVITY ").append(selectivity);
}
if (comment != null) {
buff.append(" COMMENT ").append(StringUtils.quoteStringSQL(comment));
}
if (checkConstraint != null) {
buff.append(" CHECK ").append(checkConstraintSQL);
}
return buff.toString();
}
public boolean isNullable() {
return nullable;
}
public void setOriginalSQL(String original) {
originalSQL = original;
}
public String getOriginalSQL() {
return originalSQL;
}
public Expression getDefaultExpression() {
return defaultExpression;
}
public boolean isAutoIncrement() {
return autoIncrement;
}
/**
* Set the autoincrement flag and related properties of this column.
*
* @param autoInc the new autoincrement flag
* @param start the sequence start value
* @param increment the sequence increment
*/
public void setAutoIncrement(boolean autoInc, long start, long increment) {
this.autoIncrement = autoInc;
this.start = start;
this.increment = increment;
this.nullable = false;
if (autoInc) {
convertNullToDefault = true;
}
}
public void setConvertNullToDefault(boolean convert) {
this.convertNullToDefault = convert;
}
/**
* Rename the column. This method will only set the column name to the new
* value.
*
* @param newName the new column name
*/
public void rename(String newName) {
this.name = newName;
}
public void setSequence(Sequence sequence) {
this.sequence = sequence;
}
public Sequence getSequence() {
return sequence;
}
/**
* Get the selectivity of the column. Selectivity 100 means values are
* unique, 10 means every distinct value appears 10 times on average.
*
* @return the selectivity
*/
public int getSelectivity() {
return selectivity == 0 ? Constants.SELECTIVITY_DEFAULT : selectivity;
}
/**
* Set the new selectivity of a column.
*
* @param selectivity the new value
*/
public void setSelectivity(int selectivity) {
selectivity = selectivity < 0 ? 0 : (selectivity > 100 ? 100 : selectivity);
this.selectivity = selectivity;
}
/**
* Add a check constraint expression to this column. An existing check
* constraint constraint is added using AND.
*
* @param session the session
* @param expr the (additional) constraint
*/
public void addCheckConstraint(Session session, Expression expr) {
resolver = new SingleColumnResolver(this);
synchronized (this) {
String oldName = name;
if (name == null) {
name = "VALUE";
}
expr.mapColumns(resolver, 0);
name = oldName;
}
expr = expr.optimize(session);
resolver.setValue(ValueNull.INSTANCE);
// check if the column is mapped
synchronized (this) {
expr.getValue(session);
}
if (checkConstraint == null) {
checkConstraint = expr;
} else {
checkConstraint = new ConditionAndOr(ConditionAndOr.AND, checkConstraint, expr);
}
checkConstraintSQL = getCheckConstraintSQL(session, name);
}
/**
* Get the check constraint expression for this column if set.
*
* @param session the session
* @param asColumnName the column name to use
* @return the constraint expression
*/
public Expression getCheckConstraint(Session session, String asColumnName) {
if (checkConstraint == null) {
return null;
}
Parser parser = session.createParser();
String sql;
synchronized (this) {
String oldName = name;
name = asColumnName;
sql = checkConstraint.getSQL();
name = oldName;
}
Expression expr = parser.parseExpression(sql);
return expr;
}
String getDefaultSQL() {
return defaultExpression == null ? null : defaultExpression.getSQL();
}
int getPrecisionAsInt() {
return MathUtils.convertLongToInt(precision);
}
DataType getDataType() {
return DataType.getDataType(type);
}
/**
* Get the check constraint SQL snippet.
*
* @param session the session
* @param asColumnName the column name to use
* @return the SQL snippet
*/
String getCheckConstraintSQL(Session session, String asColumnName) {
Expression constraint = getCheckConstraint(session, asColumnName);
return constraint == null ? "" : constraint.getSQL();
}
public void setComment(String comment) {
this.comment = comment;
}
public String getComment() {
return comment;
}
public void setPrimaryKey(boolean primaryKey) {
this.primaryKey = primaryKey;
}
/**
* Visit the default expression, the check constraint, and the sequence (if
* any).
*
* @param visitor the visitor
* @return true if every visited expression returned true, or if there are
* no expressions
*/
boolean isEverything(ExpressionVisitor visitor) {
if (visitor.getType() == ExpressionVisitor.GET_DEPENDENCIES) {
if (sequence != null) {
visitor.getDependencies().add(sequence);
}
}
if (defaultExpression != null && !defaultExpression.isEverything(visitor)) {
return false;
}
if (checkConstraint != null && !checkConstraint.isEverything(visitor)) {
return false;
}
return true;
}
public boolean isPrimaryKey() {
return primaryKey;
}
public String toString() {
return getFullName(); //return name;
}
/**
* Check whether the new column is of the same type and not more restricted
* than this column.
*
* @param newColumn the new (target) column
* @return true if the new column is compatible
*/
public boolean isWideningConversion(Column newColumn) {
if (type != newColumn.type) {
return false;
}
if (precision > newColumn.precision) {
return false;
}
if (scale != newColumn.scale) {
return false;
}
if (nullable && !newColumn.nullable) {
return false;
}
if (convertNullToDefault != newColumn.convertNullToDefault) {
return false;
}
if (primaryKey != newColumn.primaryKey) {
return false;
}
if (autoIncrement || newColumn.autoIncrement) {
return false;
}
if (checkConstraint != null || newColumn.checkConstraint != null) {
return false;
}
if (convertNullToDefault || newColumn.convertNullToDefault) {
return false;
}
if (defaultExpression != null || newColumn.defaultExpression != null) {
return false;
}
if (isComputed || newColumn.isComputed) {
return false;
}
return true;
}
/**
* Copy the data of the source column into the current column.
*
* @param source the source column
*/
public void copy(Column source) {
checkConstraint = source.checkConstraint;
checkConstraintSQL = source.checkConstraintSQL;
displaySize = source.displaySize;
name = source.name;
precision = source.precision;
scale = source.scale;
// table is not set
// columnId is not set
nullable = source.nullable;
defaultExpression = source.defaultExpression;
originalSQL = source.originalSQL;
// autoIncrement, start, increment is not set
convertNullToDefault = source.convertNullToDefault;
sequence = source.sequence;
comment = source.comment;
computeTableFilter = source.computeTableFilter;
isComputed = source.isComputed;
selectivity = source.selectivity;
primaryKey = source.primaryKey;
columnFamilyName = source.columnFamilyName;
columnFamilyNameeAsBytes = source.columnFamilyNameeAsBytes;
}
}