org.apache.flink.table.delegation

Interface Parser

@PublicEvolving
public interface Parser

Provides methods for parsing SQL objects from a SQL string.

Method Summary

Modifier and Type	Method and Description
String[]	getCompletionHints(String statement, int position) Returns completion hints for the given statement at the given cursor position.
List<Operation>	parse(String statement) Entry point for parsing SQL queries expressed as a String.
org.apache.flink.table.catalog.UnresolvedIdentifier	parseIdentifier(String identifier) Entry point for parsing SQL identifiers expressed as a String.
org.apache.flink.table.expressions.ResolvedExpression	parseSqlExpression(String sqlExpression, org.apache.flink.table.types.logical.RowType inputRowType, org.apache.flink.table.types.logical.LogicalType outputType) Entry point for parsing SQL expressions expressed as a String.

Method Detail

parse

List<Operation> parse(String statement)

Entry point for parsing SQL queries expressed as a String.

Note:If the created Operation is a QueryOperation it must be in a form that will be understood by the Planner.translate(List) method.

The produced Operation trees should already be validated.

Parameters:

statement - the SQL statement to evaluate

Returns:

parsed queries as trees of relational Operations

Throws:

SqlParserException - when failed to parse the statement

parseIdentifier

org.apache.flink.table.catalog.UnresolvedIdentifier parseIdentifier(String identifier)

Entry point for parsing SQL identifiers expressed as a String.

Parameters:

identifier - the SQL identifier to parse

Returns:

parsed identifier

Throws:

SqlParserException - when failed to parse the identifier

parseSqlExpression

org.apache.flink.table.expressions.ResolvedExpression parseSqlExpression(String sqlExpression,
                                                                         org.apache.flink.table.types.logical.RowType inputRowType,
                                                                         @Nullable
                                                                         org.apache.flink.table.types.logical.LogicalType outputType)

Entry point for parsing SQL expressions expressed as a String.

Parameters:

sqlExpression - the SQL expression to parse

inputRowType - the fields available in the SQL expression

outputType - expected top-level output type if available

Returns:

resolved expression

Throws:

SqlParserException - when failed to parse the sql expression

getCompletionHints

String[] getCompletionHints(String statement,
                            int position)

Returns completion hints for the given statement at the given cursor position. The completion happens case insensitively.

Parameters:

statement - Partial or slightly incorrect SQL statement

position - cursor position

Returns:

completion hints that fit at the current cursor position