Examples with SqlUpdate org.apache.calcite.sql.SqlUpdate used on opensource projects

Example 11 with SqlUpdate

use of org.apache.calcite.sql.SqlUpdate in project calcite by apache.

the class SqlValidatorImpl method rewriteMerge.

private void rewriteMerge(SqlMerge call) {
    SqlNodeList selectList;
    SqlUpdate updateStmt = call.getUpdateCall();
    if (updateStmt != null) {
        // if we have an update statement, just clone the select list
        // from the update statement's source since it's the same as
        // what we want for the select list of the merge source -- '*'
        // followed by the update set expressions
        selectList = SqlNode.clone(updateStmt.getSourceSelect().getSelectList());
    } else {
        // otherwise, just use select *
        selectList = new SqlNodeList(SqlParserPos.ZERO);
        selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
    }
    SqlNode targetTable = call.getTargetTable();
    if (call.getAlias() != null) {
        targetTable = SqlValidatorUtil.addAlias(targetTable, call.getAlias().getSimple());
    }
    // Provided there is an insert substatement, the source select for
    // the merge is a left outer join between the source in the USING
    // clause and the target table; otherwise, the join is just an
    // inner join.  Need to clone the source table reference in order
    // for validation to work
    SqlNode sourceTableRef = call.getSourceTableRef();
    SqlInsert insertCall = call.getInsertCall();
    JoinType joinType = (insertCall == null) ? JoinType.INNER : JoinType.LEFT;
    final SqlNode leftJoinTerm = SqlNode.clone(sourceTableRef);
    SqlNode outerJoin = new SqlJoin(SqlParserPos.ZERO, leftJoinTerm, SqlLiteral.createBoolean(false, SqlParserPos.ZERO), joinType.symbol(SqlParserPos.ZERO), targetTable, JoinConditionType.ON.symbol(SqlParserPos.ZERO), call.getCondition());
    SqlSelect select = new SqlSelect(SqlParserPos.ZERO, null, selectList, outerJoin, null, null, null, null, null, null, null);
    call.setSourceSelect(select);
    // that via the from clause on the select
    if (insertCall != null) {
        SqlCall valuesCall = (SqlCall) insertCall.getSource();
        SqlCall rowCall = valuesCall.operand(0);
        selectList = new SqlNodeList(rowCall.getOperandList(), SqlParserPos.ZERO);
        final SqlNode insertSource = SqlNode.clone(sourceTableRef);
        select = new SqlSelect(SqlParserPos.ZERO, null, selectList, insertSource, null, null, null, null, null, null, null);
        insertCall.setSource(select);
    }
}