/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.dialect;
import java.sql.CallableStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import org.hibernate.JDBCException;
import org.hibernate.NullPrecedence;
import org.hibernate.boot.TempTableDdlTransactionHandling;
import org.hibernate.cfg.Environment;
import org.hibernate.dialect.function.NoArgSQLFunction;
import org.hibernate.dialect.function.StandardSQLFunction;
import org.hibernate.dialect.identity.IdentityColumnSupport;
import org.hibernate.dialect.identity.MySQLIdentityColumnSupport;
import org.hibernate.dialect.pagination.AbstractLimitHandler;
import org.hibernate.dialect.pagination.LimitHandler;
import org.hibernate.dialect.pagination.LimitHelper;
import org.hibernate.dialect.unique.MySQLUniqueDelegate;
import org.hibernate.dialect.unique.UniqueDelegate;
import org.hibernate.engine.spi.RowSelection;
import org.hibernate.exception.LockAcquisitionException;
import org.hibernate.exception.LockTimeoutException;
import org.hibernate.exception.spi.SQLExceptionConversionDelegate;
import org.hibernate.hql.spi.id.IdTableSupportStandardImpl;
import org.hibernate.hql.spi.id.MultiTableBulkIdStrategy;
import org.hibernate.hql.spi.id.local.AfterUseAction;
import org.hibernate.hql.spi.id.local.LocalTemporaryTableBulkIdStrategy;
import org.hibernate.internal.util.JdbcExceptionHelper;
import org.hibernate.internal.util.StringHelper;
import org.hibernate.mapping.Column;
import org.hibernate.type.StandardBasicTypes;
/**
* An SQL dialect for MySQL (prior to 5.x).
*
* @author Gavin King
*/
@SuppressWarnings("deprecation")
public class MySQLDialect extends Dialect {
private final UniqueDelegate uniqueDelegate;
private MySQLStorageEngine storageEngine;
private static final LimitHandler LIMIT_HANDLER = new AbstractLimitHandler() {
@Override
public String processSql(String sql, RowSelection selection) {
final boolean hasOffset = LimitHelper.hasFirstRow( selection );
return sql + (hasOffset ? " limit ?, ?" : " limit ?");
}
@Override
public boolean supportsLimit() {
return true;
}
};
/**
* Constructs a MySQLDialect
*/
public MySQLDialect() {
super();
String storageEngine = Environment.getProperties().getProperty( Environment.STORAGE_ENGINE );
if(storageEngine == null) {
storageEngine = System.getProperty( Environment.STORAGE_ENGINE );
}
if(storageEngine == null) {
this.storageEngine = getDefaultMySQLStorageEngine();
}
else if( "innodb".equals( storageEngine.toLowerCase() ) ) {
this.storageEngine = InnoDBStorageEngine.INSTANCE;
}
else if( "myisam".equals( storageEngine.toLowerCase() ) ) {
this.storageEngine = MyISAMStorageEngine.INSTANCE;
}
else {
throw new UnsupportedOperationException( "The " + storageEngine + " storage engine is not supported!" );
}
registerColumnType( Types.BIT, "bit" );
registerColumnType( Types.BIGINT, "bigint" );
registerColumnType( Types.SMALLINT, "smallint" );
registerColumnType( Types.TINYINT, "tinyint" );
registerColumnType( Types.INTEGER, "integer" );
registerColumnType( Types.CHAR, "char(1)" );
registerColumnType( Types.FLOAT, "float" );
registerColumnType( Types.DOUBLE, "double precision" );
registerColumnType( Types.BOOLEAN, "bit" ); // HHH-6935
registerColumnType( Types.DATE, "date" );
registerColumnType( Types.TIME, "time" );
registerColumnType( Types.TIMESTAMP, "datetime" );
registerColumnType( Types.VARBINARY, "longblob" );
registerColumnType( Types.VARBINARY, 16777215, "mediumblob" );
registerColumnType( Types.VARBINARY, 65535, "blob" );
registerColumnType( Types.VARBINARY, 255, "tinyblob" );
registerColumnType( Types.BINARY, "binary($l)" );
registerColumnType( Types.LONGVARBINARY, "longblob" );
registerColumnType( Types.LONGVARBINARY, 16777215, "mediumblob" );
registerColumnType( Types.NUMERIC, "decimal($p,$s)" );
registerColumnType( Types.BLOB, "longblob" );
// registerColumnType( Types.BLOB, 16777215, "mediumblob" );
// registerColumnType( Types.BLOB, 65535, "blob" );
registerColumnType( Types.CLOB, "longtext" );
registerColumnType( Types.NCLOB, "longtext" );
// registerColumnType( Types.CLOB, 16777215, "mediumtext" );
// registerColumnType( Types.CLOB, 65535, "text" );
registerVarcharTypes();
registerFunction( "ascii", new StandardSQLFunction( "ascii", StandardBasicTypes.INTEGER ) );
registerFunction( "bin", new StandardSQLFunction( "bin", StandardBasicTypes.STRING ) );
registerFunction( "char_length", new StandardSQLFunction( "char_length", StandardBasicTypes.LONG ) );
registerFunction( "character_length", new StandardSQLFunction( "character_length", StandardBasicTypes.LONG ) );
registerFunction( "lcase", new StandardSQLFunction( "lcase" ) );
registerFunction( "lower", new StandardSQLFunction( "lower" ) );
registerFunction( "ltrim", new StandardSQLFunction( "ltrim" ) );
registerFunction( "ord", new StandardSQLFunction( "ord", StandardBasicTypes.INTEGER ) );
registerFunction( "quote", new StandardSQLFunction( "quote" ) );
registerFunction( "reverse", new StandardSQLFunction( "reverse" ) );
registerFunction( "rtrim", new StandardSQLFunction( "rtrim" ) );
registerFunction( "soundex", new StandardSQLFunction( "soundex" ) );
registerFunction( "space", new StandardSQLFunction( "space", StandardBasicTypes.STRING ) );
registerFunction( "ucase", new StandardSQLFunction( "ucase" ) );
registerFunction( "upper", new StandardSQLFunction( "upper" ) );
registerFunction( "unhex", new StandardSQLFunction( "unhex", StandardBasicTypes.STRING ) );
registerFunction( "abs", new StandardSQLFunction( "abs" ) );
registerFunction( "sign", new StandardSQLFunction( "sign", StandardBasicTypes.INTEGER ) );
registerFunction( "acos", new StandardSQLFunction( "acos", StandardBasicTypes.DOUBLE ) );
registerFunction( "asin", new StandardSQLFunction( "asin", StandardBasicTypes.DOUBLE ) );
registerFunction( "atan", new StandardSQLFunction( "atan", StandardBasicTypes.DOUBLE ) );
registerFunction( "cos", new StandardSQLFunction( "cos", StandardBasicTypes.DOUBLE ) );
registerFunction( "cot", new StandardSQLFunction( "cot", StandardBasicTypes.DOUBLE ) );
registerFunction( "crc32", new StandardSQLFunction( "crc32", StandardBasicTypes.LONG ) );
registerFunction( "exp", new StandardSQLFunction( "exp", StandardBasicTypes.DOUBLE ) );
registerFunction( "ln", new StandardSQLFunction( "ln", StandardBasicTypes.DOUBLE ) );
registerFunction( "log", new StandardSQLFunction( "log", StandardBasicTypes.DOUBLE ) );
registerFunction( "log2", new StandardSQLFunction( "log2", StandardBasicTypes.DOUBLE ) );
registerFunction( "log10", new StandardSQLFunction( "log10", StandardBasicTypes.DOUBLE ) );
registerFunction( "pi", new NoArgSQLFunction( "pi", StandardBasicTypes.DOUBLE ) );
registerFunction( "rand", new NoArgSQLFunction( "rand", StandardBasicTypes.DOUBLE ) );
registerFunction( "sin", new StandardSQLFunction( "sin", StandardBasicTypes.DOUBLE ) );
registerFunction( "sqrt", new StandardSQLFunction( "sqrt", StandardBasicTypes.DOUBLE ) );
registerFunction( "stddev", new StandardSQLFunction("std", StandardBasicTypes.DOUBLE) );
registerFunction( "tan", new StandardSQLFunction( "tan", StandardBasicTypes.DOUBLE ) );
registerFunction( "radians", new StandardSQLFunction( "radians", StandardBasicTypes.DOUBLE ) );
registerFunction( "degrees", new StandardSQLFunction( "degrees", StandardBasicTypes.DOUBLE ) );
registerFunction( "ceiling", new StandardSQLFunction( "ceiling", StandardBasicTypes.INTEGER ) );
registerFunction( "ceil", new StandardSQLFunction( "ceil", StandardBasicTypes.INTEGER ) );
registerFunction( "floor", new StandardSQLFunction( "floor", StandardBasicTypes.INTEGER ) );
registerFunction( "round", new StandardSQLFunction( "round" ) );
registerFunction( "datediff", new StandardSQLFunction( "datediff", StandardBasicTypes.INTEGER ) );
registerFunction( "timediff", new StandardSQLFunction( "timediff", StandardBasicTypes.TIME ) );
registerFunction( "date_format", new StandardSQLFunction( "date_format", StandardBasicTypes.STRING ) );
registerFunction( "curdate", new NoArgSQLFunction( "curdate", StandardBasicTypes.DATE ) );
registerFunction( "curtime", new NoArgSQLFunction( "curtime", StandardBasicTypes.TIME ) );
registerFunction( "current_date", new NoArgSQLFunction( "current_date", StandardBasicTypes.DATE, false ) );
registerFunction( "current_time", new NoArgSQLFunction( "current_time", StandardBasicTypes.TIME, false ) );
registerFunction( "current_timestamp", new NoArgSQLFunction( "current_timestamp", StandardBasicTypes.TIMESTAMP, false ) );
registerFunction( "date", new StandardSQLFunction( "date", StandardBasicTypes.DATE ) );
registerFunction( "day", new StandardSQLFunction( "day", StandardBasicTypes.INTEGER ) );
registerFunction( "dayofmonth", new StandardSQLFunction( "dayofmonth", StandardBasicTypes.INTEGER ) );
registerFunction( "dayname", new StandardSQLFunction( "dayname", StandardBasicTypes.STRING ) );
registerFunction( "dayofweek", new StandardSQLFunction( "dayofweek", StandardBasicTypes.INTEGER ) );
registerFunction( "dayofyear", new StandardSQLFunction( "dayofyear", StandardBasicTypes.INTEGER ) );
registerFunction( "from_days", new StandardSQLFunction( "from_days", StandardBasicTypes.DATE ) );
registerFunction( "from_unixtime", new StandardSQLFunction( "from_unixtime", StandardBasicTypes.TIMESTAMP ) );
registerFunction( "hour", new StandardSQLFunction( "hour", StandardBasicTypes.INTEGER ) );
registerFunction( "last_day", new StandardSQLFunction( "last_day", StandardBasicTypes.DATE ) );
registerFunction( "localtime", new NoArgSQLFunction( "localtime", StandardBasicTypes.TIMESTAMP ) );
registerFunction( "localtimestamp", new NoArgSQLFunction( "localtimestamp", StandardBasicTypes.TIMESTAMP ) );
registerFunction( "microseconds", new StandardSQLFunction( "microseconds", StandardBasicTypes.INTEGER ) );
registerFunction( "minute", new StandardSQLFunction( "minute", StandardBasicTypes.INTEGER ) );
registerFunction( "month", new StandardSQLFunction( "month", StandardBasicTypes.INTEGER ) );
registerFunction( "monthname", new StandardSQLFunction( "monthname", StandardBasicTypes.STRING ) );
registerFunction( "now", new NoArgSQLFunction( "now", StandardBasicTypes.TIMESTAMP ) );
registerFunction( "quarter", new StandardSQLFunction( "quarter", StandardBasicTypes.INTEGER ) );
registerFunction( "second", new StandardSQLFunction( "second", StandardBasicTypes.INTEGER ) );
registerFunction( "sec_to_time", new StandardSQLFunction( "sec_to_time", StandardBasicTypes.TIME ) );
registerFunction( "sysdate", new NoArgSQLFunction( "sysdate", StandardBasicTypes.TIMESTAMP ) );
registerFunction( "time", new StandardSQLFunction( "time", StandardBasicTypes.TIME ) );
registerFunction( "timestamp", new StandardSQLFunction( "timestamp", StandardBasicTypes.TIMESTAMP ) );
registerFunction( "time_to_sec", new StandardSQLFunction( "time_to_sec", StandardBasicTypes.INTEGER ) );
registerFunction( "to_days", new StandardSQLFunction( "to_days", StandardBasicTypes.LONG ) );
registerFunction( "unix_timestamp", new StandardSQLFunction( "unix_timestamp", StandardBasicTypes.LONG ) );
registerFunction( "utc_date", new NoArgSQLFunction( "utc_date", StandardBasicTypes.STRING ) );
registerFunction( "utc_time", new NoArgSQLFunction( "utc_time", StandardBasicTypes.STRING ) );
registerFunction( "utc_timestamp", new NoArgSQLFunction( "utc_timestamp", StandardBasicTypes.STRING ) );
registerFunction( "week", new StandardSQLFunction( "week", StandardBasicTypes.INTEGER ) );
registerFunction( "weekday", new StandardSQLFunction( "weekday", StandardBasicTypes.INTEGER ) );
registerFunction( "weekofyear", new StandardSQLFunction( "weekofyear", StandardBasicTypes.INTEGER ) );
registerFunction( "year", new StandardSQLFunction( "year", StandardBasicTypes.INTEGER ) );
registerFunction( "yearweek", new StandardSQLFunction( "yearweek", StandardBasicTypes.INTEGER ) );
registerFunction( "hex", new StandardSQLFunction( "hex", StandardBasicTypes.STRING ) );
registerFunction( "oct", new StandardSQLFunction( "oct", StandardBasicTypes.STRING ) );
registerFunction( "octet_length", new StandardSQLFunction( "octet_length", StandardBasicTypes.LONG ) );
registerFunction( "bit_length", new StandardSQLFunction( "bit_length", StandardBasicTypes.LONG ) );
registerFunction( "bit_count", new StandardSQLFunction( "bit_count", StandardBasicTypes.LONG ) );
registerFunction( "encrypt", new StandardSQLFunction( "encrypt", StandardBasicTypes.STRING ) );
registerFunction( "md5", new StandardSQLFunction( "md5", StandardBasicTypes.STRING ) );
registerFunction( "sha1", new StandardSQLFunction( "sha1", StandardBasicTypes.STRING ) );
registerFunction( "sha", new StandardSQLFunction( "sha", StandardBasicTypes.STRING ) );
registerFunction( "concat", new StandardSQLFunction( "concat", StandardBasicTypes.STRING ) );
getDefaultProperties().setProperty( Environment.MAX_FETCH_DEPTH, "2" );
getDefaultProperties().setProperty( Environment.STATEMENT_BATCH_SIZE, DEFAULT_BATCH_SIZE );
uniqueDelegate = new MySQLUniqueDelegate( this );
}
protected void registerVarcharTypes() {
registerColumnType( Types.VARCHAR, "longtext" );
// registerColumnType( Types.VARCHAR, 16777215, "mediumtext" );
// registerColumnType( Types.VARCHAR, 65535, "text" );
registerColumnType( Types.VARCHAR, 255, "varchar($l)" );
registerColumnType( Types.LONGVARCHAR, "longtext" );
}
@Override
public String getAddColumnString() {
return "add column";
}
@Override
public boolean qualifyIndexName() {
return false;
}
@Override
public String getAddForeignKeyConstraintString(
String constraintName,
String[] foreignKey,
String referencedTable,
String[] primaryKey,
boolean referencesPrimaryKey) {
final String cols = StringHelper.join( ", ", foreignKey );
final String referencedCols = StringHelper.join( ", ", primaryKey );
return String.format(
" add constraint %s foreign key (%s) references %s (%s)",
constraintName,
cols,
referencedTable,
referencedCols
);
}
@Override
public boolean supportsLimit() {
return true;
}
@Override
public String getDropForeignKeyString() {
return " drop foreign key ";
}
@Override
public LimitHandler getLimitHandler() {
return LIMIT_HANDLER;
}
@Override
public String getLimitString(String sql, boolean hasOffset) {
return sql + (hasOffset ? " limit ?, ?" : " limit ?");
}
@Override
public char closeQuote() {
return '`';
}
@Override
public char openQuote() {
return '`';
}
@Override
public boolean canCreateCatalog() {
return true;
}
@Override
public String[] getCreateCatalogCommand(String catalogName) {
return new String[] { "create database " + catalogName };
}
@Override
public String[] getDropCatalogCommand(String catalogName) {
return new String[] { "drop database " + catalogName };
}
@Override
public boolean canCreateSchema() {
return false;
}
@Override
public String[] getCreateSchemaCommand(String schemaName) {
throw new UnsupportedOperationException( "MySQL does not support dropping creating/dropping schemas in the JDBC sense" );
}
@Override
public String[] getDropSchemaCommand(String schemaName) {
throw new UnsupportedOperationException( "MySQL does not support dropping creating/dropping schemas in the JDBC sense" );
}
@Override
public boolean supportsIfExistsBeforeTableName() {
return true;
}
@Override
public String getSelectGUIDString() {
return "select uuid()";
}
@Override
public String getTableComment(String comment) {
return " comment='" + comment + "'";
}
@Override
public String getColumnComment(String comment) {
return " comment '" + comment + "'";
}
@Override
public MultiTableBulkIdStrategy getDefaultMultiTableBulkIdStrategy() {
return new LocalTemporaryTableBulkIdStrategy(
new IdTableSupportStandardImpl() {
@Override
public String getCreateIdTableCommand() {
return "create temporary table if not exists";
}
@Override
public String getDropIdTableCommand() {
return "drop temporary table";
}
},
AfterUseAction.DROP,
TempTableDdlTransactionHandling.NONE
);
}
@Override
public String getCastTypeName(int code) {
switch ( code ) {
case Types.BOOLEAN:
return "char";
case Types.INTEGER:
case Types.BIGINT:
case Types.SMALLINT:
return smallIntegerCastTarget();
case Types.FLOAT:
case Types.REAL: {
return floatingPointNumberCastTarget();
}
case Types.NUMERIC:
return fixedPointNumberCastTarget();
case Types.VARCHAR:
return "char";
case Types.VARBINARY:
return "binary";
default:
return super.getCastTypeName( code );
}
}
/**
* Determine the cast target for {@link Types#INTEGER}, {@link Types#BIGINT} and {@link Types#SMALLINT}
*
* @return The proper cast target type.
*/
protected String smallIntegerCastTarget() {
return "signed";
}
/**
* Determine the cast target for {@link Types#FLOAT} and {@link Types#REAL} (DOUBLE)
*
* @return The proper cast target type.
*/
protected String floatingPointNumberCastTarget() {
// MySQL does not allow casting to DOUBLE nor FLOAT, so we have to cast these as DECIMAL.
// MariaDB does allow casting to DOUBLE, although not FLOAT.
return fixedPointNumberCastTarget();
}
/**
* Determine the cast target for {@link Types#NUMERIC}
*
* @return The proper cast target type.
*/
protected String fixedPointNumberCastTarget() {
// NOTE : the precision/scale are somewhat arbitrary choices, but MySQL/MariaDB
// effectively require *some* values
return "decimal(" + Column.DEFAULT_PRECISION + "," + Column.DEFAULT_SCALE + ")";
}
@Override
public boolean supportsCurrentTimestampSelection() {
return true;
}
@Override
public boolean isCurrentTimestampSelectStringCallable() {
return false;
}
@Override
public String getCurrentTimestampSelectString() {
return "select now()";
}
@Override
public int registerResultSetOutParameter(CallableStatement statement, int col) throws SQLException {
return col;
}
@Override
public ResultSet getResultSet(CallableStatement ps) throws SQLException {
boolean isResultSet = ps.execute();
while ( !isResultSet && ps.getUpdateCount() != -1 ) {
isResultSet = ps.getMoreResults();
}
return ps.getResultSet();
}
@Override
public UniqueDelegate getUniqueDelegate() {
return uniqueDelegate;
}
@Override
public boolean supportsRowValueConstructorSyntax() {
return true;
}
@Override
public String renderOrderByElement(String expression, String collation, String order, NullPrecedence nulls) {
final StringBuilder orderByElement = new StringBuilder();
if ( nulls != NullPrecedence.NONE ) {
// Workaround for NULLS FIRST / LAST support.
orderByElement.append( "case when " ).append( expression ).append( " is null then " );
if ( nulls == NullPrecedence.FIRST ) {
orderByElement.append( "0 else 1" );
}
else {
orderByElement.append( "1 else 0" );
}
orderByElement.append( " end, " );
}
// Nulls precedence has already been handled so passing NONE value.
orderByElement.append( super.renderOrderByElement( expression, collation, order, NullPrecedence.NONE ) );
return orderByElement.toString();
}
// locking support
@Override
public String getForUpdateString() {
return " for update";
}
@Override
public String getWriteLockString(int timeout) {
return " for update";
}
@Override
public String getReadLockString(int timeout) {
return " lock in share mode";
}
// Overridden informational metadata ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@Override
public boolean supportsEmptyInList() {
return false;
}
@Override
public boolean areStringComparisonsCaseInsensitive() {
return true;
}
@Override
public boolean supportsLobValueChangePropogation() {
// note: at least my local MySQL 5.1 install shows this not working...
return false;
}
@Override
public boolean supportsSubqueryOnMutatingTable() {
return false;
}
@Override
public boolean supportsLockTimeouts() {
// yes, we do handle "lock timeout" conditions in the exception conversion delegate,
// but that's a hardcoded lock timeout period across the whole entire MySQL database.
// MySQL does not support specifying lock timeouts as part of the SQL statement, which is really
// what this meta method is asking.
return false;
}
@Override
public SQLExceptionConversionDelegate buildSQLExceptionConversionDelegate() {
return new SQLExceptionConversionDelegate() {
@Override
public JDBCException convert(SQLException sqlException, String message, String sql) {
final String sqlState = JdbcExceptionHelper.extractSqlState( sqlException );
if ( "41000".equals( sqlState ) ) {
return new LockTimeoutException( message, sqlException, sql );
}
if ( "40001".equals( sqlState ) ) {
return new LockAcquisitionException( message, sqlException, sql );
}
return null;
}
};
}
@Override
public String getNotExpression(String expression) {
return "not (" + expression + ")";
}
@Override
public IdentityColumnSupport getIdentityColumnSupport() {
return new MySQLIdentityColumnSupport();
}
@Override
public boolean isJdbcLogWarningsEnabledByDefault() {
return false;
}
@Override
public boolean supportsCascadeDelete() {
return storageEngine.supportsCascadeDelete();
}
@Override
public String getTableTypeString() {
return storageEngine.getTableTypeString( getEngineKeyword());
}
protected String getEngineKeyword() {
return "type";
}
@Override
public boolean hasSelfReferentialForeignKeyBug() {
return storageEngine.hasSelfReferentialForeignKeyBug();
}
@Override
public boolean dropConstraints() {
return storageEngine.dropConstraints();
}
protected MySQLStorageEngine getDefaultMySQLStorageEngine() {
return MyISAMStorageEngine.INSTANCE;
}
}