/*
* Copyright 2004-2023 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.mode;
import java.util.HashMap;
import java.util.StringJoiner;
import org.h2.api.ErrorCode;
import org.h2.command.Parser;
import org.h2.engine.Constants;
import org.h2.engine.RightOwner;
import org.h2.engine.SessionLocal;
import org.h2.engine.User;
import org.h2.expression.Expression;
import org.h2.expression.ValueExpression;
import org.h2.expression.function.CurrentGeneralValueSpecification;
import org.h2.expression.function.RandFunction;
import org.h2.index.Index;
import org.h2.message.DbException;
import org.h2.schema.Schema;
import org.h2.server.pg.PgServer;
import org.h2.table.Column;
import org.h2.table.Table;
import org.h2.util.StringUtils;
import org.h2.value.TypeInfo;
import org.h2.value.Value;
import org.h2.value.ValueArray;
import org.h2.value.ValueBigint;
import org.h2.value.ValueBoolean;
import org.h2.value.ValueInteger;
import org.h2.value.ValueNull;
import org.h2.value.ValueVarchar;
/**
* Functions for {@link org.h2.engine.Mode.ModeEnum#PostgreSQL} compatibility
* mode.
*/
public final class FunctionsPostgreSQL extends ModeFunction {
private static final int CURRENT_DATABASE = 3001;
private static final int CURRTID2 = CURRENT_DATABASE + 1;
private static final int FORMAT_TYPE = CURRTID2 + 1;
private static final int HAS_DATABASE_PRIVILEGE = FORMAT_TYPE + 1;
private static final int HAS_SCHEMA_PRIVILEGE = HAS_DATABASE_PRIVILEGE + 1;
private static final int HAS_TABLE_PRIVILEGE = HAS_SCHEMA_PRIVILEGE + 1;
private static final int LASTVAL = HAS_TABLE_PRIVILEGE + 1;
private static final int VERSION = LASTVAL + 1;
private static final int OBJ_DESCRIPTION = VERSION + 1;
private static final int PG_ENCODING_TO_CHAR = OBJ_DESCRIPTION + 1;
private static final int PG_GET_EXPR = PG_ENCODING_TO_CHAR + 1;
private static final int PG_GET_INDEXDEF = PG_GET_EXPR + 1;
private static final int PG_GET_USERBYID = PG_GET_INDEXDEF + 1;
private static final int PG_POSTMASTER_START_TIME = PG_GET_USERBYID + 1;
private static final int PG_RELATION_SIZE = PG_POSTMASTER_START_TIME + 1;
private static final int PG_TABLE_IS_VISIBLE = PG_RELATION_SIZE + 1;
private static final int SET_CONFIG = PG_TABLE_IS_VISIBLE + 1;
private static final int ARRAY_TO_STRING = SET_CONFIG + 1;
private static final int PG_STAT_GET_NUMSCANS = ARRAY_TO_STRING + 1;
private static final int TO_DATE = PG_STAT_GET_NUMSCANS + 1;
private static final int TO_TIMESTAMP = TO_DATE + 1;
private static final int GEN_RANDOM_UUID = TO_TIMESTAMP + 1;
private static final HashMap<String, FunctionInfo> FUNCTIONS = new HashMap<>(32);
static {
FUNCTIONS.put("CURRENT_DATABASE",
new FunctionInfo("CURRENT_DATABASE", CURRENT_DATABASE, 0, Value.VARCHAR, true, false));
FUNCTIONS.put("CURRTID2", new FunctionInfo("CURRTID2", CURRTID2, 2, Value.INTEGER, true, false));
FUNCTIONS.put("FORMAT_TYPE", new FunctionInfo("FORMAT_TYPE", FORMAT_TYPE, 2, Value.VARCHAR, false, true));
FUNCTIONS.put("HAS_DATABASE_PRIVILEGE", new FunctionInfo("HAS_DATABASE_PRIVILEGE", HAS_DATABASE_PRIVILEGE,
VAR_ARGS, Value.BOOLEAN, true, false));
FUNCTIONS.put("HAS_SCHEMA_PRIVILEGE",
new FunctionInfo("HAS_SCHEMA_PRIVILEGE", HAS_SCHEMA_PRIVILEGE, VAR_ARGS, Value.BOOLEAN, true, false));
FUNCTIONS.put("HAS_TABLE_PRIVILEGE",
new FunctionInfo("HAS_TABLE_PRIVILEGE", HAS_TABLE_PRIVILEGE, VAR_ARGS, Value.BOOLEAN, true, false));
FUNCTIONS.put("LASTVAL", new FunctionInfo("LASTVAL", LASTVAL, 0, Value.BIGINT, true, false));
FUNCTIONS.put("VERSION", new FunctionInfo("VERSION", VERSION, 0, Value.VARCHAR, true, false));
FUNCTIONS.put("OBJ_DESCRIPTION",
new FunctionInfo("OBJ_DESCRIPTION", OBJ_DESCRIPTION, VAR_ARGS, Value.VARCHAR, true, false));
FUNCTIONS.put("PG_ENCODING_TO_CHAR",
new FunctionInfo("PG_ENCODING_TO_CHAR", PG_ENCODING_TO_CHAR, 1, Value.VARCHAR, true, true));
FUNCTIONS.put("PG_GET_EXPR", //
new FunctionInfo("PG_GET_EXPR", PG_GET_EXPR, VAR_ARGS, Value.VARCHAR, true, true));
FUNCTIONS.put("PG_GET_INDEXDEF",
new FunctionInfo("PG_GET_INDEXDEF", PG_GET_INDEXDEF, VAR_ARGS, Value.VARCHAR, true, false));
FUNCTIONS.put("PG_GET_USERBYID",
new FunctionInfo("PG_GET_USERBYID", PG_GET_USERBYID, 1, Value.VARCHAR, true, false));
FUNCTIONS.put("PG_POSTMASTER_START_TIME", //
new FunctionInfo("PG_POSTMASTER_START_TIME", PG_POSTMASTER_START_TIME, 0, Value.TIMESTAMP_TZ, true,
false));
FUNCTIONS.put("PG_RELATION_SIZE",
new FunctionInfo("PG_RELATION_SIZE", PG_RELATION_SIZE, VAR_ARGS, Value.BIGINT, true, false));
FUNCTIONS.put("PG_TABLE_IS_VISIBLE",
new FunctionInfo("PG_TABLE_IS_VISIBLE", PG_TABLE_IS_VISIBLE, 1, Value.BOOLEAN, true, false));
FUNCTIONS.put("SET_CONFIG", new FunctionInfo("SET_CONFIG", SET_CONFIG, 3, Value.VARCHAR, true, false));
FUNCTIONS.put("ARRAY_TO_STRING",
new FunctionInfo("ARRAY_TO_STRING", ARRAY_TO_STRING, VAR_ARGS, Value.VARCHAR, false, true));
FUNCTIONS.put("PG_STAT_GET_NUMSCANS",
new FunctionInfo("PG_STAT_GET_NUMSCANS", PG_STAT_GET_NUMSCANS, 1, Value.INTEGER, true, true));
FUNCTIONS.put("TO_DATE", new FunctionInfo("TO_DATE", TO_DATE, 2, Value.DATE, true, true));
FUNCTIONS.put("TO_TIMESTAMP",
new FunctionInfo("TO_TIMESTAMP", TO_TIMESTAMP, 2, Value.TIMESTAMP_TZ, true, true));
FUNCTIONS.put("GEN_RANDOM_UUID",
new FunctionInfo("GEN_RANDOM_UUID", GEN_RANDOM_UUID, 0, Value.UUID, true, false));
}
/**
* Returns mode-specific function for a given name, or {@code null}.
*
* @param upperName
* the upper-case name of a function
* @return the function with specified name or {@code null}
*/
public static FunctionsPostgreSQL getFunction(String upperName) {
FunctionInfo info = FUNCTIONS.get(upperName);
if (info != null) {
return new FunctionsPostgreSQL(info);
}
return null;
}
private FunctionsPostgreSQL(FunctionInfo info) {
super(info);
}
@Override
protected void checkParameterCount(int len) {
int min, max;
switch (info.type) {
case HAS_DATABASE_PRIVILEGE:
case HAS_SCHEMA_PRIVILEGE:
case HAS_TABLE_PRIVILEGE:
min = 2;
max = 3;
break;
case OBJ_DESCRIPTION:
case PG_RELATION_SIZE:
min = 1;
max = 2;
break;
case PG_GET_INDEXDEF:
if (len != 1 && len != 3) {
throw DbException.get(ErrorCode.INVALID_PARAMETER_COUNT_2, info.name, "1, 3");
}
return;
case PG_GET_EXPR:
case ARRAY_TO_STRING:
min = 2;
max = 3;
break;
default:
throw DbException.getInternalError("type=" + info.type);
}
if (len < min || len > max) {
throw DbException.get(ErrorCode.INVALID_PARAMETER_COUNT_2, info.name, min + ".." + max);
}
}
@Override
public Expression optimize(SessionLocal session) {
switch (info.type) {
case CURRENT_DATABASE:
return new CurrentGeneralValueSpecification(CurrentGeneralValueSpecification.CURRENT_CATALOG)
.optimize(session);
case GEN_RANDOM_UUID:
return new RandFunction(null, RandFunction.RANDOM_UUID).optimize(session);
default:
boolean allConst = optimizeArguments(session);
type = TypeInfo.getTypeInfo(info.returnDataType);
if (allConst) {
return ValueExpression.get(getValue(session));
}
}
return this;
}
@Override
public Value getValue(SessionLocal session) {
Value[] values = getArgumentsValues(session, args);
if (values == null) {
return ValueNull.INSTANCE;
}
Value v0 = getNullOrValue(session, args, values, 0);
Value v1 = getNullOrValue(session, args, values, 1);
Value v2 = getNullOrValue(session, args, values, 2);
Value result;
switch (info.type) {
case CURRTID2:
// Not implemented
result = ValueInteger.get(1);
break;
case FORMAT_TYPE:
result = v0 != ValueNull.INSTANCE ? ValueVarchar.get(PgServer.formatType(v0.getInt())) //
: ValueNull.INSTANCE;
break;
case HAS_DATABASE_PRIVILEGE:
case HAS_SCHEMA_PRIVILEGE:
case HAS_TABLE_PRIVILEGE:
case PG_TABLE_IS_VISIBLE:
// Not implemented
result = ValueBoolean.TRUE;
break;
case LASTVAL:
result = session.getLastIdentity();
if (result == ValueNull.INSTANCE) {
throw DbException.get(ErrorCode.CURRENT_SEQUENCE_VALUE_IS_NOT_DEFINED_IN_SESSION_1, "lastval()");
}
result = result.convertToBigint(null);
break;
case VERSION:
result = ValueVarchar
.get("PostgreSQL " + Constants.PG_VERSION + " server protocol using H2 " + Constants.FULL_VERSION);
break;
case OBJ_DESCRIPTION:
// Not implemented
result = ValueNull.INSTANCE;
break;
case PG_ENCODING_TO_CHAR:
result = ValueVarchar.get(encodingToChar(v0.getInt()));
break;
case PG_GET_EXPR:
// Not implemented
result = ValueNull.INSTANCE;
break;
case PG_GET_INDEXDEF:
result = getIndexdef(session, v0.getInt(), v1, v2);
break;
case PG_GET_USERBYID:
result = ValueVarchar.get(getUserbyid(session, v0.getInt()));
break;
case PG_POSTMASTER_START_TIME:
result = session.getDatabase().getSystemSession().getSessionStart();
break;
case PG_RELATION_SIZE:
// Optional second argument is ignored
result = relationSize(session, v0);
break;
case SET_CONFIG:
// Not implemented
result = v1.convertTo(Value.VARCHAR);
break;
case ARRAY_TO_STRING:
if (v0 == ValueNull.INSTANCE || v1 == ValueNull.INSTANCE) {
result = ValueNull.INSTANCE;
break;
}
StringJoiner joiner = new StringJoiner(v1.getString());
if (v0.getValueType() != Value.ARRAY) {
throw DbException.getInvalidValueException("ARRAY_TO_STRING array", v0);
}
String nullString = null;
if (v2 != null) {
nullString = v2.getString();
}
for (Value v : ((ValueArray) v0).getList()) {
if (v != ValueNull.INSTANCE) {
joiner.add(v.getString());
} else if (nullString != null) {
joiner.add(nullString);
}
}
result = ValueVarchar.get(joiner.toString());
break;
case PG_STAT_GET_NUMSCANS:
// Not implemented
result = ValueInteger.get(0);
break;
case TO_DATE:
result = ToDateParser.toDate(session, v0.getString(), v1.getString()).convertToDate(session);
break;
case TO_TIMESTAMP:
result = ToDateParser.toTimestampTz(session, v0.getString(), v1.getString());
break;
default:
throw DbException.getInternalError("type=" + info.type);
}
return result;
}
private static String encodingToChar(int code) {
switch (code) {
case 0:
return "SQL_ASCII";
case 6:
return "UTF8";
case 8:
return "LATIN1";
default:
// This function returns empty string for unknown encodings
return code < 40 ? "UTF8" : "";
}
}
private static Value getIndexdef(SessionLocal session, int indexId, Value ordinalPosition, Value pretty) {
for (Schema schema : session.getDatabase().getAllSchemasNoMeta()) {
for (Index index : schema.getAllIndexes()) {
if (index.getId() == indexId) {
if (!index.getTable().isHidden()) {
int ordinal;
if (ordinalPosition == null || (ordinal = ordinalPosition.getInt()) == 0) {
return ValueVarchar.get(index.getCreateSQL());
}
Column[] columns;
if (ordinal >= 1 && ordinal <= (columns = index.getColumns()).length) {
return ValueVarchar.get(columns[ordinal - 1].getName());
}
}
break;
}
}
}
return ValueNull.INSTANCE;
}
private static String getUserbyid(SessionLocal session, int uid) {
User u = session.getUser();
String name;
search: {
if (u.getId() == uid) {
name = u.getName();
break search;
} else {
if (u.isAdmin()) {
for (RightOwner rightOwner : session.getDatabase().getAllUsersAndRoles()) {
if (rightOwner.getId() == uid) {
name = rightOwner.getName();
break search;
}
}
}
}
return "unknown (OID=" + uid + ')';
}
if (session.getDatabase().getSettings().databaseToLower) {
name = StringUtils.toLowerEnglish(name);
}
return name;
}
private static Value relationSize(SessionLocal session, Value tableOidOrName) {
Table t;
if (tableOidOrName.getValueType() == Value.INTEGER) {
int tid = tableOidOrName.getInt();
for (Schema schema : session.getDatabase().getAllSchemasNoMeta()) {
for (Table table : schema.getAllTablesAndViews(session)) {
if (tid == table.getId()) {
t = table;
break;
}
}
}
return ValueNull.INSTANCE;
} else {
t = new Parser(session).parseTableName(tableOidOrName.getString());
}
return ValueBigint.get(t.getDiskSpaceUsed());
}
}