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BLOB Data Types Syntax

The BLOB data types hold binary, character or custom format data of unspecified size.For more information, see [fblangref50-datatypes-bnrytypes].

BLOB Data Types Syntax
<blob_datatype> ::=
    BLOB [SUB_TYPE {subtype_num | subtype_name}]
    [SEGMENT SIZE seglen] [CHARACTER SET charset]
  | BLOB [(seglen [, subtype_num])]
  | BLOB [(, subtype_num)]
Table 1. Arguments for the Blob Data Types Syntax
Argument Description

charset

Character set (ignored for subtypes other than TEXT/1).

subtype_num

BLOB subtype number

subtype_name

BLOB subtype mnemonic name;this can be TEXT, BINARY, or one of the (other) standard or custom names defined in RDB$TYPES for RDB$FIELD_NAME = 'RDB$FIELD_SUB_TYPE'.

seglen

Segment size, cannot be greater than 65,535, defaults to 80 when not specified.See also [fblangref50-datatypes-seg-size]

If the SUB_TYPE and CHARACTER SET clauses are absent, then subtype BINARY (or 0) is used.If the SUB_TYPE clause is absent and the CHARACTER SET clause is present, then subtype TEXT (or 1) is used.

Array Data Types Syntax

The array data types hold multiple scalar values in a single or multi-dimensional array.For more information, see [fblangref50-datatypes-array]

Array Data Types Syntax
<array_datatype> ::=
    {SMALLINT | INT[EGER] | BIGINT | INT128} <array_dim>
  | {REAL | FLOAT [(bin_prec)] | DOUBLE PRECISION} <array_dim>
  | DECFLOAT [(dec_prec)] <array_dim>
  | BOOLEAN <array_dim>
  | DATE <array_dim>
  | TIME [{WITHOUT | WITH} TIME ZONE] <array_dim>
  | TIMESTAMP [{WITHOUT | WITH} TIME ZONE] <array_dim>
  | {DECIMAL | DEC | NUMERIC} [(precision [, scale])] <array_dim>
  | {VARCHAR | {CHAR | CHARACTER} VARYING} (length)
    <array_dim> [CHARACTER SET charset]
  | {CHAR | CHARACTER} [(length)] <array_dim>
    [CHARACTER SET charset]
  | {NCHAR | NATIONAL {CHARACTER | CHAR}} VARYING (length)
    <array_dim>
  | {NCHAR | NATIONAL {CHARACTER | CHAR}}
    [(length)] <array_dim>
  | BINARY [(length)] <array_dim>
  | {VARBINARY | BINARY VARYING} (length) <array_dim>

<array_dim> ::= '[' [m:]n [,[m:]n ...] ']'
Table 1. Arguments for the Array Data Types Syntax
Argument Description

array_dim

Array dimensions

bin_prec

Binary precision, default is 24.

1 - 24: 32-bit single precision
25 - 53: 64-bit double precision (synonym of DOUBLE PRECISION)

dec_prec

Decimal precision of DECFLOAT, either 16 or 34;default is 34

precision

Numeric precision in decimal digits.From 1 to 38

scale

Scale, or number of decimals.From 0 to 38.It must be less than or equal to precision

length

The maximum length of a string, in characters, or — for BINARY and VARBINARY — bytes;optional for fixed-width character types, defaults to 1

charset

Character set

m, n

Integer numbers defining the index range of an array dimension