Data Type Declaration Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 3.12.1. Scalar Data Types Syntax . . . . . . . . . . . 12.2. BLOB Data Types Syntax. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 3.12.3. Array Data Types Syntax. . . . . . . . . . . point of view, the following names are the same: fullname FULLNAME FuLlNaMe FullName Regular name syntax ::= | | | _ | $ ::=

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point of view, the following names are the same: fullname FULLNAME FuLlNaMe FullName Regular name syntax ::= | | | _ | $ ::= syntax ::= "[ …]"  A delimited identifier separators, to quote identifiers and to mark the limits of string literals or comments. Operator Syntax ::= | |

. . . . . 53 3.11. Syntax der Datentyp-Deklaration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3.11.1. Syntax für Skalardatentypen . . . . . . 55 3.11.2. Syntax der BLOB-Datentypen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 3.11.3. Syntax der Array-Datentypen . . Firebird unterstützt zwei Arten von Kommentaren: block und in-line. Chapter 2. SQL Sprachstruktur 22 Syntax ::= | ::= /* [

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3.1.1. Für Firebird 2 empfohlene Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . als Synonym für GENERATOR benutzen. Es wird in der Tat empfohlen, in neuem SQL-Code die SEQUENCE-Syntax zu verwenden. Auch wenn das Schlüsselwort “SEQUENCE” die Betonung auf die Erzeugung einer Serie Datenbankobjekt. Man kann einen Generator erzeugen und dann mit der Sequenz-Syntax auf ihn zugreifen und umgekehrt. Dies ist die bevorzugte Syntax zur Erzeugung einer Sequenz bzw. eines Generators in Firebird 2:

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.1.1. Firebird 2 recommended syntax. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . synonym for GENERATOR in Firebird 2 and up. In fact it is recommended that you use the SEQUENCE syntax in new code. Although the word “sequence” puts the emphasis on the series of values generated whereas database object. You can create a generator and access it using the sequence syntax, and vice versa. This is the preferred syntax for creating a generator/sequence in Firebird 2: CREATE SEQUENCE SeqTest;

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8.1.1. URL-like Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . client library — and by extension, isql — supports a variety of connection strings. Connection String Syntax ::= [server_spec]{filepath | db_alias} ::= host[/{port | service}]: include either entry by default. 8.1.1. URL-like Syntax Firebird 3.0 introduced a unified URL-like syntax for the remote server specification. In this syntax, the first part specifies the name of the protocol

the “ordinal number” (degree) in an ORDER BY clause, when the output list uses SELECT * FROM ... syntax, the column list will be expanded and taken into account when determining which column the number error. If you actually want the former behaviour, you have two alternatives: • Specify the full syntax gbak -REPLACE_DATABASE. There is a new shortcut for the - REPLACE_DATABASE switch: gbak -REP OR keyword must be present in either the full or the abbreviated form. Warning If you use the full syntax, you are expected to know what this restore mode actually means and have some recovery strategy available

NULL If you want to know whether a variable, field or other expression is NULL, use the following syntax: IS [NOT] NULL Examples: if ( MyField is null ) then YourString = 'Dunno' select null delete from Phonebook where PhoneNum is null Do not use “… = NULL” to test for nullness. This syntax is illegal in Firebird versions up to 1.5.n, and gives the wrong result in Firebird 2 and up: it NULLs would always come last in any sorted set, period. Firebird 1.5 introduced the NULLS FIRST/LAST syntax, so you could force them to the top or bottom. To sum it all up: Table 6. NULLs placement in ordered

rare occasions where you have to be aware of the difference. 6.1.3. XNET connection strings The syntax for XNET URLs is: {xnet}:// Since XNET is a purely local protocol, you can’t include language, were case-sensitive or contained spaces or special characters [1]. SQL-92 introduced a new syntax to make any of them legal, provided that the identifiers are defined within pairs of double-quote database upgrade instructions from Firebird 3 and higher • Updated SQL user management statement syntax to be more complete • Merged URL-style and TCP/IP protocol description • Added replacement images

введённые таким образом будут иметь кодировку OCTETS по умолчанию, но вводный синтаксис (introducer syntax) может быть использован для принудительной интерпретации строки в другом наборе символов. Синтаксис: который начинается с префикса подчеркивания «_». Это известно как вводный синтаксис (Introducer syntax). Его цель заключается в информировании Firebird о том, как интерпретировать и хранить входящую строку INTO cars VALUES ('Ford', 'T', 1908, 'USA', 850); -- обратите внимание на префикс '_' (introducer syntax) INSERT INTO People VALUES (_ISO8859_1 'Hans-Jörg Schäfer'); INSERT .