hexadecimal INTEGERs in the above example are automatically cast to BIGINT before being inserted into the table. However, this happens after the numerical value is determined, so 0x80000000 (8 digits) and four digits, including two digits after the decimal point; that is, it can have up to two digits before the point and no more than two digits after the point. If the number 3.1415 is written to a column milliseconds precision. Deci- milliseconds can be specified but they are rounded to the nearest integer before any operation is performed • The EXTRACT() function returns up to deci-milliseconds precision with

hexadecimal INTEGERs in the above example are automatically cast to BIGINT before being inserted into the table. However, this happens after the numerical value is determined, so 0x80000000 (8 digits) and four digits, including two digits after the decimal point; that is, it can have up to two digits before the point and no more than Chapter 3. Data Types and Subtypes 34 two digits after the point. If 60 -120 Updating the Time Zone Database Time zones are often changed: of course, when it happens, it is desirable to update the time zone database as soon as possible. Firebird stores WITH TIME

Shadows The command to activate a database shadow is: gfix -ac[tivate_shadow] shadow_file_name  Before Firebird 3, the command line switch was -⁠ac[tivate]. This makes the shadow file the new database active can lead to corruption of the shadow. Make sure the database file is really unavailable before activating a shadow. Once a shadow file has been activated, you can see the fact that there are unavailable database shadows, for a specific database, is: gfix -k[ill_shadow] database_name  Before Firebird 3, the command line switch was -⁠k[ill]. In the event that a database running with shadow

will be initialised to NULL except where a default value is in effect or a value is assigned by a “before insert” trigger. • If you add a column to a table that already has records, the fields added to only contains numbers, not `NaN or infinities.) • The empty string is ordered lexicographically before every other string. Therefore, S >= '' is true whatever the value of S. • Every value equals itself ()”, with A indeed not present in the list (so you’d expect a clear true result), but the list happens to contain one or more NULLs.  Be especially careful if you use NOT IN with a subselect instead

represent different pages in the database. As each byte has 8 bits, we have a total of 32,608 pages before we need a new PIP. In a brand new database, a hex dump of the first few bytes of page 1, the first transaction id is different to the other records we inserted. This is because we added a COMMIT before we inserted this row. The NULL data expands from the above to: ff 00 00 00 happens when a table with more than 32 fields is created. In this case, I’m using a record with 40 columns

. . . . . 13 4.4.1. Before Insert trigger, version 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.4.2. Before Insert trigger, version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.4.3. Before Insert trigger, version 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . integers), and you would insert 1000 rows per second, it would take around 300 million years (!) before it rolls over. As it is pretty unlikely mankind will still walk on this planet by then (and still

probably futile, anyway, since some details will escape, whatever you try. 4.2. Protecting User Data Before continuing with other discussions relating to encryption of Firebird data, I do want to highlight key. When you start the computer you have to mount the encrypted volume and supply the secret key before the data can be accessed. This additional, and necessarily manual, step in the start up process So, let’s look at how things would work if Firebird were to encrypt the metadata in a database… Before the database could be accessed the secret key would need to be supplied. Giving the decryption key

version LI-V2.5.0.26074 Firebird 2.5 gbak: ERROR:requires both input and output filenames gbak:Exiting before completion due to errors tux> echo $? 1 This displays the current version of gbak, and after displaying need to use in order to avoid ambiguity. Once you have specified the absolute minimum — the part before the opening '[' — you can use as much of what follows as you wish. For example, to use the -b[ackup_database] have a two-phase transaction (across two different databases) that failed because a server died before the commit, but after the changes were made, you have a limbo transaction. This switch forces the

............ 41 1 Chapter 1 Known Compatibility Issues D. Yemanov Please study this chapter before attempting to install any servers. It is intended as a set of alerts to those who are migrating Firebird clear about the effects of having a wrong value in this variable, you should remove or update it before you begin installing Firebird 2.1. After doing so, you should also check that the old value is no upgrade the security database using the provided script in order to keep your existing user logins. Before you begin the necessary alterations to commission an existing security database on the Firebird 2

maintained, and regularly updated, by members of the Firebird documentation project. Important Before you read on, verify that this guide matches your Firebird version. This guide covers versions 2.0– corresponding Quick Start Guide at http://www. firebirdsql.org/en/documentation/. Some warnings before you start • Firebird 2.0.2 was recalled due to a regression; if you use it, upgrade to 2.0.3 or switch to the other architecture later; your applications and databases will keep func- tioning like before. For Linux, Superserver download packages start with FirebirdSS, Classic packages with FirebirdCS