and end with the */ character pair. Text in block comments may be of any length and can occupy multiple lines. In-line comments start with a pair of hyphen characters, -- and continue up to the end of integer is converted back. The method of storing fixed-point data in the DBMS depends on several factors: declared precision, database dialect, declaration type. Table 2. Method of Physical Storage for the rule is during string concatenation. Implicit Conversion During String Concatenation When multiple data elements are being concatenated, all non-string data will undergo implicit conversion to string

and end with the */ character pair. Text in block comments may be of any length and can occupy multiple lines. In-line comments start with a pair of hyphen characters, -- and continue up to the end of integer is converted back. The method of storing fixed-point data in the database depends on several factors: declared precision, database dialect, declaration type. Table 5. Method of Physical Storage for the rule is during string concatenation. Implicit Conversion During String Concatenation When multiple data elements are being concatenated, all non-string data will undergo implicit conversion to string

with a special user name .......................................................... 30 Installing Multiple Servers ....................................................................................... installation. Running Multiple Instances The configuration parameter CreateInternalWindow in firebird.conf is now deprecated. You no longer need to disable it if you need to run multiple instances of Firebird for anyone to write non-compliant statements in new code! Multiple Hits to Same Column Now Illegal It is no longer allowed to make multiple “hits” on the same column in an INSERT or UPDATE statement

platforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.3. Installing multiple servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . to edit the scripts and make some manual adjustments. 3.3. Installing multiple servers Firebird allows the operation of multiple servers on a single machine. It can also run concurrently with Firebird Firebird 1.x or InterBase servers. Setting this up is not a beginner’s task though. If you need to run multiple servers on the same machine, the second and subsequent servers must be installed and configured

.................................................................................. 9 Installing multiple servers ....................................................................................... manual adjustments. Firebird 2.0 and 2.1 Quick Start 11 Installing multiple servers Firebird 2 allows the operation of multiple servers on a single machine. It can also run concurrently with Firebird Firebird 1.x or InterBase servers. Setting this up is not a beginner's task though. If you need to run multiple servers, consult the Installation Notes chapter of the Release Notes, and have the Firebird 1.5

Firebird 1.5 and up, unique keys and unique indices allow NULLs, and what’s more: they even allow multiple NULLs. With a single-column key or index, you can insert as many NULLs as you want in that column each non-NULL value only once. If the key or index is defined on multiple columns in Firebird 1.5 and higher: • You can insert multiple rows where all the key columns are NULL; • But as soon as one or Indices, NULLs are ◦ not allowed in Firebird 1.0; ◦ allowed (even multiple) in Firebird 1.5 and higher. • In Foreign Key columns, multiple NULLs are allowed. • If a CHECK constraint evaluates to NULL, the

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Multiple File Databases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Introduction 2 Chapter 2. Database Structure When you create a new database, be it single or multiple file, a number of things happen: • The database file(s) are created; • The header page is formatted Pages (page type 0x05) and so on. There is a discussion of each page type below. 2.2. Multiple File Databases A multiple file Firebird database is almost identical to the single file database except it has

remotely. SMP (symmetrical multi-processor) sup- port. Better performance in case of a small number of multiple connections that do not influence each other. No SMP support. On multi-processor Windows ma- chines command-line tools (gsec, gbak etc.) it works just fine. By contrast, direct database connections - even multiple - under a Linux Classic server are completely safe. Firebird 1.0 Quick Start Guide 11 Default line and the prompt will change from SQL> to CON>. This enables you to spread long statements over multiple lines. If you hit Enter after your statement and you've forgotten the semicolon, just type it on

number @1 in derived table @2 -104 336397221 dsql_derived_field_dup_name Column @1 was specified multiple times for derived table @2 -104 336397222 dsql_derived_alias_select Internal dsql error: alias subquery_err No subqueries permitted for VIEW WITH CHECK OPTION -811 335544652 sing_select_err Multiple rows in singleton select -816 335544651 ext_readonly_err Cannot insert because the file is readonly 335740937 gfix_trn_req Number of transactions per sweep required -901 336330761 gbak_multi_source_dest Multiple sources or destinations specified -901 335544330 bad_tpb_content Invalid parameter in transaction

(with a minimum of 2048 bytes) and will only create files it needs. tux> # Backup the database to multiple files. tux> gbak -backup employee /backups/emp.a.fbk 600m /backups/emp.b.fbk 600m The sizes after database above being restored from the two files dumped above: tux> # Restore the database from multiple files. tux> gfix -shut -tran 60 employee Chapter 6. Backup & Restore Recipes 19 tux> gbak -replace applies to my installation only and means that the following simple backup script will work. If multiple file databases were used, more coding would be required to take a backup using external tools.