/*
* Copyright 2014-2015 the original author or authors
*
* Licensed under the Apache License, Version 2.0 (the “License”);
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an “AS IS” BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.wplatform.ddal.engine;
import java.util.HashMap;
import com.wplatform.ddal.util.New;
import com.wplatform.ddal.util.StringUtils;
/**
* The compatibility modes. There is a fixed set of modes (for example
* PostgreSQL, MySQL). Each mode has different settings.
*/
public class Mode {
/**
* The name of the PostgreSQL mode.
*/
public static final String POSTGRE_SQL = "PostgreSQL";
/**
* The name of the Oracle mode.
*/
public static final String ORACLE = "Oracle";
/**
* The name of the MySQL mode.
*/
public static final String MY_SQL = "MySQL";
/**
* The name of the MSSQLServer mode.
*/
public static final String MSSQL_SERVER = "MSSQLServer";
/**
* The name of the HSQLDB mode.
*/
public static final String HSQLDB = "HSQLDB";
/**
* The name of the Derby mode.
*/
public static final String DERBY = "Derby";
/**
* The name of the DB2 mode.
*/
public static final String DB2 = "DB2";
/**
* The name of the REGULAR mode.
*/
public static final String REGULAR = "REGULAR";
private static final HashMap<String, Mode> MODES = New.hashMap();
// Modes are also documented in the features section
static {
Mode mode = new Mode(REGULAR);
mode.nullConcatIsNull = true;
add(mode);
mode = new Mode(DB2);
mode.aliasColumnName = true;
mode.supportOffsetFetch = true;
mode.sysDummy1 = true;
mode.isolationLevelInSelectOrInsertStatement = true;
add(mode);
mode = new Mode(DERBY);
mode.aliasColumnName = true;
mode.uniqueIndexSingleNull = true;
mode.supportOffsetFetch = true;
mode.sysDummy1 = true;
mode.isolationLevelInSelectOrInsertStatement = true;
add(mode);
mode = new Mode(HSQLDB);
mode.aliasColumnName = true;
mode.convertOnlyToSmallerScale = true;
mode.nullConcatIsNull = true;
mode.uniqueIndexSingleNull = true;
mode.allowPlusForStringConcat = true;
add(mode);
mode = new Mode(MSSQL_SERVER);
mode.aliasColumnName = true;
mode.squareBracketQuotedNames = true;
mode.uniqueIndexSingleNull = true;
mode.allowPlusForStringConcat = true;
mode.swapConvertFunctionParameters = true;
add(mode);
mode = new Mode(MY_SQL);
mode.convertInsertNullToZero = true;
mode.indexDefinitionInCreateTable = true;
mode.lowerCaseIdentifiers = true;
mode.onDuplicateKeyUpdate = true;
add(mode);
mode = new Mode(ORACLE);
mode.aliasColumnName = true;
mode.convertOnlyToSmallerScale = true;
mode.uniqueIndexSingleNullExceptAllColumnsAreNull = true;
mode.treatEmptyStringsAsNull = true;
add(mode);
mode = new Mode(POSTGRE_SQL);
mode.aliasColumnName = true;
mode.nullConcatIsNull = true;
mode.supportOffsetFetch = true;
mode.systemColumns = true;
mode.logIsLogBase10 = true;
mode.serialColumnIsNotPK = true;
add(mode);
}
private final String name;
/**
* When enabled, aliased columns (as in SELECT ID AS I FROM TEST) return the
* alias (I in this case) in ResultSetMetaData.getColumnName() and 'null' in
* getTableName(). If disabled, the real column name (ID in this case) and
* table name is returned.
*/
public boolean aliasColumnName;
/**
* When inserting data, if a column is defined to be NOT NULL and NULL is
* inserted, then a 0 (or empty string, or the current timestamp for
* timestamp columns) value is used. Usually, this operation is not allowed
* and an exception is thrown.
*/
public boolean convertInsertNullToZero;
/**
* When converting the scale of decimal data, the number is only converted
* if the new scale is smaller than the current scale. Usually, the scale is
* converted and 0s are added if required.
*/
public boolean convertOnlyToSmallerScale;
/**
* Creating indexes in the CREATE TABLE statement is allowed using
* <code>INDEX(..)</code> or <code>KEY(..)</code>.
* Example: <code>create table test(id int primary key, name varchar(255),
* key idx_name(name));</code>
*/
public boolean indexDefinitionInCreateTable;
/**
* Meta data calls return identifiers in lower case.
*/
public boolean lowerCaseIdentifiers;
/**
* Concatenation with NULL results in NULL. Usually, NULL is treated as an
* empty string if only one of the operands is NULL, and NULL is only
* returned if both operands are NULL.
*/
public boolean nullConcatIsNull;
/**
* Identifiers may be quoted using square brackets as in [Test].
*/
public boolean squareBracketQuotedNames;
/**
* Support for the syntax
* [OFFSET .. ROW|ROWS] [FETCH FIRST .. ROW|ROWS ONLY]
* as an alternative for LIMIT .. OFFSET.
*/
public boolean supportOffsetFetch = true;
/**
* The system columns 'CTID' and 'OID' are supported.
*/
public boolean systemColumns;
/**
* For unique indexes, NULL is distinct. That means only one row with NULL
* in one of the columns is allowed.
*/
public boolean uniqueIndexSingleNull;
/**
* When using unique indexes, multiple rows with NULL in all columns
* are allowed, however it is not allowed to have multiple rows with the
* same values otherwise.
*/
public boolean uniqueIndexSingleNullExceptAllColumnsAreNull;
/**
* Empty strings are treated like NULL values. Useful for Oracle emulation.
*/
public boolean treatEmptyStringsAsNull;
/**
* Support the pseudo-table SYSIBM.SYSDUMMY1.
*/
public boolean sysDummy1;
/**
* Text can be concatenated using '+'.
*/
public boolean allowPlusForStringConcat;
/**
* The function LOG() uses base 10 instead of E.
*/
public boolean logIsLogBase10;
/**
* SERIAL and BIGSERIAL columns are not automatically primary keys.
*/
public boolean serialColumnIsNotPK;
/**
* Swap the parameters of the CONVERT function.
*/
public boolean swapConvertFunctionParameters;
/**
* can set the isolation level using WITH {RR|RS|CS|UR}
*/
public boolean isolationLevelInSelectOrInsertStatement;
/**
* MySQL style INSERT ... ON DUPLICATE KEY UPDATE ...
*/
public boolean onDuplicateKeyUpdate;
private Mode(String name) {
this.name = name;
}
private static void add(Mode mode) {
MODES.put(StringUtils.toUpperEnglish(mode.name), mode);
}
/**
* Get the mode with the given name.
*
* @param name the name of the mode
* @return the mode object
*/
public static Mode getInstance(String name) {
return MODES.get(StringUtils.toUpperEnglish(name));
}
public String getName() {
return name;
}
}