Package org.apache.calcite.sql

Class SqlDataTypeSpec

  • All Implemented Interfaces:
    java.lang.Cloneable
    public class SqlDataTypeSpec
extends SqlNode
    Represents a SQL data type specification in a parse tree.

    A SqlDataTypeSpec is immutable; once created, you cannot change any of the fields.

    todo: This should really be a subtype of SqlCall.

    In its full glory, we will have to support complex type expressions like:

    ROW(
    NUMBER(5, 2) NOT NULL AS foo,
    ROW(BOOLEAN AS b, MyUDT NOT NULL AS i) AS rec)

    Currently it only supports simple datatypes like CHAR, VARCHAR and DOUBLE, with optional precision and scale.

    • Field Detail

      • collectionsTypeName

        private final SqlIdentifier collectionsTypeName

      • scale

        private final int scale

      • precision

        private final int precision

      • charSetName

        private final java.lang.String charSetName

      • timeZone

        private final java.util.TimeZone timeZone

      • nullable

        private java.lang.Boolean nullable
        Whether data type is allows nulls.

        Nullable is nullable! Null means "not specified". E.g. CAST(x AS INTEGER) preserves has the same nullability as x.

    • Constructor Detail

      • SqlDataTypeSpec

        public SqlDataTypeSpec​(SqlIdentifier typeName,
                       int precision,
                       int scale,
                       java.lang.String charSetName,
                       java.util.TimeZone timeZone,
                       SqlParserPos pos)
        Creates a type specification representing a regular, non-collection type.

      • SqlDataTypeSpec

        public SqlDataTypeSpec​(SqlIdentifier collectionsTypeName,
                       SqlIdentifier typeName,
                       int precision,
                       int scale,
                       java.lang.String charSetName,
                       SqlParserPos pos)
        Creates a type specification representing a collection type.

      • SqlDataTypeSpec

        public SqlDataTypeSpec​(SqlIdentifier collectionsTypeName,
                       SqlIdentifier typeName,
                       int precision,
                       int scale,
                       java.lang.String charSetName,
                       java.util.TimeZone timeZone,
                       java.lang.Boolean nullable,
                       SqlParserPos pos)
        Creates a type specification that has no base type.

      • SqlDataTypeSpec

        public SqlDataTypeSpec​(SqlIdentifier collectionsTypeName,
                       SqlIdentifier typeName,
                       SqlIdentifier baseTypeName,
                       int precision,
                       int scale,
                       java.lang.String charSetName,
                       java.util.TimeZone timeZone,
                       java.lang.Boolean nullable,
                       SqlParserPos pos)
        Creates a type specification.

    • Method Detail

      • getCollectionsTypeName

        public SqlIdentifier getCollectionsTypeName()

      • getScale

        public int getScale()

      • getPrecision

        public int getPrecision()

      • getCharSetName

        public java.lang.String getCharSetName()

      • getTimeZone

        public java.util.TimeZone getTimeZone()

      • getNullable

        public java.lang.Boolean getNullable()

      • withNullable

        public SqlDataTypeSpec withNullable​(java.lang.Boolean nullable)
        Returns a copy of this data type specification with a given nullability.

      • getComponentTypeSpec

        public SqlDataTypeSpec getComponentTypeSpec()
        Returns a new SqlDataTypeSpec corresponding to the component type if the type spec is a collections type spec.
        Collection types are ARRAY and MULTISET.

      • unparse

        public void unparse​(SqlWriter writer,
                    int leftPrec,
                    int rightPrec)
        Description copied from class: SqlNode
        Writes a SQL representation of this node to a writer.

        The leftPrec and rightPrec parameters give us enough context to decide whether we need to enclose the expression in parentheses. For example, we need parentheses around "2 + 3" if preceded by "5 *". This is because the precedence of the "*" operator is greater than the precedence of the "+" operator.

        The algorithm handles left- and right-associative operators by giving them slightly different left- and right-precedence.

        If SqlWriter.isAlwaysUseParentheses() is true, we use parentheses even when they are not required by the precedence rules.

        For the details of this algorithm, see SqlCall.unparse(org.apache.calcite.sql.SqlWriter, int, int).

        Specified by:
        unparse in class SqlNode
        Parameters:
        writer - Target writer
        leftPrec - The precedence of the SqlNode immediately preceding this node in a depth-first scan of the parse tree
        rightPrec - The precedence of the SqlNode immediately

      • accept

        public <R> R accept​(SqlVisitor<R> visitor)
        Description copied from class: SqlNode
        Accepts a generic visitor.

        Implementations of this method in subtypes simply call the appropriate visit method on the visitor object.

        The type parameter R must be consistent with the type parameter of the visitor.

        Specified by:
        accept in class SqlNode

      • equalsDeep

        public boolean equalsDeep​(SqlNode node,
                          Litmus litmus)
        Description copied from class: SqlNode
        Returns whether this node is structurally equivalent to another node. Some examples:
        • 1 + 2 is structurally equivalent to 1 + 2
        • 1 + 2 + 3 is structurally equivalent to (1 + 2) + 3, but not to 1 + (2 + 3), because the '+' operator is left-associative
        Specified by:
        equalsDeep in class SqlNode

      • deriveType

        public RelDataType deriveType​(RelDataTypeFactory typeFactory,
                              boolean nullable)
        Converts this type specification to a RelDataType.

        Does not throw an error if the type is not built-in.

        Parameters:
        nullable - Whether the type is nullable if the type specification does not explicitly state