How to use

getCastSpec

method

in

org.apache.calcite.sql.SqlDialect

@Override public SqlNode getCastSpec(RelDataType type) {
 String castSpec;
 switch (type.getSqlTypeName()) {
 case TINYINT:
  // Postgres has no tinyint (1 byte), so instead cast to smallint (2 bytes)
  castSpec = "_smallint";
  break;
 case DOUBLE:
  // Postgres has a double type but it is named differently
  castSpec = "_double precision";
  break;
 default:
  return super.getCastSpec(type);
 }
 return new SqlDataTypeSpec(new SqlIdentifier(castSpec, SqlParserPos.ZERO),
   -1, -1, null, null, SqlParserPos.ZERO);
}

@Override public SqlNode getCastSpec(RelDataType type) {
 String castSpec;
 switch (type.getSqlTypeName()) {
 case TINYINT:
  // Postgres has no tinyint (1 byte), so instead cast to smallint (2 bytes)
  castSpec = "_smallint";
  break;
 case DOUBLE:
  // Postgres has a double type but it is named differently
  castSpec = "_double precision";
  break;
 default:
  return super.getCastSpec(type);
 }
 return new SqlDataTypeSpec(new SqlIdentifier(castSpec, SqlParserPos.ZERO),
   -1, -1, null, null, SqlParserPos.ZERO);
}

@Override public SqlNode getCastSpec(RelDataType type) {
 switch (type.getSqlTypeName()) {
 case VARCHAR:
  // MySQL doesn't have a VARCHAR type, only CHAR.
  return new SqlDataTypeSpec(new SqlIdentifier("CHAR", SqlParserPos.ZERO),
    type.getPrecision(), -1, null, null, SqlParserPos.ZERO);
 case INTEGER:
  return new SqlDataTypeSpec(new SqlIdentifier("_UNSIGNED", SqlParserPos.ZERO),
    type.getPrecision(), -1, null, null, SqlParserPos.ZERO);
 }
 return super.getCastSpec(type);
}

@Override public SqlNode getCastSpec(RelDataType type) {
 switch (type.getSqlTypeName()) {
 case VARCHAR:
  // MySQL doesn't have a VARCHAR type, only CHAR.
  return new SqlDataTypeSpec(new SqlIdentifier("CHAR", SqlParserPos.ZERO),
    type.getPrecision(), -1, null, null, SqlParserPos.ZERO);
 case INTEGER:
 case BIGINT:
  return new SqlDataTypeSpec(new SqlIdentifier("_SIGNED", SqlParserPos.ZERO),
    type.getPrecision(), -1, null, null, SqlParserPos.ZERO);
 }
 return super.getCastSpec(type);
}

 return nodeList.get(0);
} else {
 nodeList.add(dialect.getCastSpec(call.getType()));

 return nodeList.get(0);
} else {
 nodeList.add(dialect.getCastSpec(call.getType()));