-
+
-
Backend Interface
-
-Backend Interface (
BKI) files are scripts that are input
-backend running in the special "bootstrap" mode that allows it to perform
-database functions without a database system already existing.
BKI files
-can therefore be used to create the database system in the first place.
-uses
BKI files to do just that: to create a database system. However,
-
BKI files are generated internally. It generates them using the files
-global1.bki.source and local1.template1.bki.source, which it finds in the
-
Postgres "library" directory. They get installed there as part of installing
-
Postgres. These .source files get build as part of the
Postgres build
-process, by a build program called
-takes as input
Postgres source files that double as
-input that builds tables and C header files that describe those
-tables.
-
-
-Related information may be found in documentation for
-and the
SQL command
CREATE DATABASE.
-
-
-
-
<acronym>BKI</acronym> File Format
-
- The
Postgres backend interprets
-
BKI files as described below. This
- description will be easier to understand if the
- global1.bki.source file is
- at hand as an example. (As explained above, this .source file isn't quite
- a
BKI file, but you'll be able to guess what
- the resulting
BKI file would be
- anyway).
-
-
-Commands are composed of a command name followed by space separated
-arguments. Arguments to a command that begin with a "$" are
-treated specially. If "$$" are the first two characters, then
-the first "$" is ignored and the argument is then processed
-normally. If the "$" is followed by space, then it is treated
-as a NULL
-value. Otherwise, the characters following the "$" are
-interpreted as the name of a macro causing the argument to be replaced
-with the macro's value. It is an error for this macro to be
-undefined.
-
-
-Macros are defined using
-define macro macro_name = macro_value
-
-and are undefined using
-undefine macro macro_name
-
-and redefined using the same syntax as define.
-
-
-Lists of general commands and macro commands
-follow.
-
-
-
-
-
General Commands
-
-
-
-
-OPEN classname
-
-
-Open the class called
-classname
-for further manipulation.
-
-
-
-
-
-
-CLOSE [classname]
-
-
-Close the open class called
-classname.
-It is an error if
-classname
-is not already opened. If no
-classname
-is given, then the currently open class is closed.
-
-
-
-
-
-
-PRINT
-
-
-Print the currently open class.
-
-
-
-
-
-
-INSERT [OID=oid_value] (value1 value2 ...)
-
-
-Insert a new instance to the open class using
-value1,
-value2,
-etc., for its attribute values and
-oid_value
-for its OID. If
-oid_value
-is not zero (0), then this value will be used as the instance's
-object identifier. Otherwise, it is an error.
-
-
-
-
-
-
-INSERT (value1 value2 ...)
-
-
-As above, but the system generates a unique object identifier.
-
-
-
-
-
-
-CREATE classname (name1 = type1 [,name2 = type2[,...]])
-
-
-Create a class named
-classname
-with the attributes given in parentheses.
-
-
-
-
-
-
-OPEN (name1 = type1 [,name2 = type2[,...]]) AS classname
-
-
-Open a class named
-classname
-for writing but do not record its existence in the system catalogs.
-(This is primarily to aid in bootstrapping.)
-
-
-
-
-
-
-DESTROY classname
-
-
-Destroy the class named
-classname.
-
-
-
-
-
-
-DEFINE INDEX indexname ON class_name USING amname
- (opclass attr | (function(attr))
-
-
-Create an index named
-indexname
-on the class named
-classname
-using the
-amname
-access method. The fields to index are called
-name1,
-name2
-etc., and the operator collections to use are
-collection_1,
-collection_2
-etc., respectively.
-
-
-
-
-
-
-
-This last sentence doesn't reference anything in the example. Should be changed to make sense. - Thomas 1998-08-04
-
-
-
-
-
-
Macro Commands
-
-
-
-
-DEFINE FUNCTION macro_name AS rettype function_name(args)
-
-
-Define a function prototype for a function named
-macro_name
-which has its value of type
-rettype
-computed from the execution
-function_name
-with the arguments
-args
-declared in a C-like manner.
-
-
-
-
-
-
-DEFINE MACRO macro_name FROM FILE filename
-
-
-Define a macro named
-macro_name
-which has its value
-read from the file called
-filename.
-
-
-
-
-
-
-
-
-
-
Debugging Commands
-
-
-This section on debugging commands was commented-out in the original documentation. Thomas 1998-08-05
-
-
-
-
-
-
-r
-
-
-Randomly print the open class.
-
-
-
-
-
-
-m -1
-
-
-Toggle display of time information.
-
-
-
-
-
-
-m 0
-
-
-Set retrievals to now.
-
-
-
-
-
-
-m 1 Jan 1 01:00:00 1988
-
-
-Set retrievals to snapshots of the specfied time.
-
-
-
-
-
-
-m 2 Jan 1 01:00:00 1988, Feb 1 01:00:00 1988
-
-
-Set retrievals to ranges of the specified times.
-Either time may be replaced with space
-if an unbounded time range is desired.
-
-
-
-
-
-
-&A classname natts name1 type1 name2 type2 ...
-
-
-Add
-natts
-attributes named
-name1,
-name2,
-etc. of
-types
-type1,
-type2,
-etc. to the class
-classname.
-
-
-
-
-
-
-&RR oldclassname newclassname
-
-
-Rename the
-oldclassname
-class to
-newclassname.
-
-
-
-
-
-
-&RA classname oldattname newattname
-classname
-oldattname
-newattname
-
-
-Rename the
-oldattname
-attribute in the class named
-classname
-to
-newattname.
-
-
-
-
-
-
-
-
-
Example
-
-The following set of commands will create the pg_opclass
-class containing the
-collection as an object with an OID of
-print out the class, and then close it.
+
<acronym>BKI</acronym> Backend Interface
+
+ Backend Interface (
BKI) files are scripts in a
+ special language that are input to the
+
Postgres backend running in the special
+ bootstrap
mode that allows it to perform database
+ functions without a database system already existing.
+
BKI files can therefore be used to create the
+ database system in the first place. (And they are probably not
+ useful for anything else.)
+
+
+ to do part of its job when creating a new database cluster. The
+ input files used by
initbd are created as
+ part of building and installing
Postgres+ by a program named genbki.sh from some
+ specially formatted C header files in the source tree. The created
+ BKI files are called global.bki (for global
+ catalogs) and template1.bki (for the catalogs
+ initially stored in the template1 database and then duplicated in
+ every created database) and are normally installed in the
+ share subdirectory of the installation tree.
+
+
+ Related information may be found in the documentation for
+
+
+
+
<acronym>BKI</acronym> File Format
+
+ This section describes how the
Postgres+ backend interprets
BKI files. This description
+ will be easier to understand if the global.bki
+ file is at hand as an example. You should also study the source
+ code of
initdb to get an idea of how the
+ backend is invoked.
+
+
+ BKI input consists of a sequence of commands. Commands are made up
+ of a number of tokens, depending on the syntax of the command.
+ Tokens are usually separated by whitespace, but need not be if
+ there is no ambiguity. There is not special command separator; the
+ next token that syntactically cannot belong to the preceeding
+ command starts a new one. (Usually you would put a new command on
+ a new line, for clarity.) Tokens can be certain key words, special
+ characters (parentheses, commas, etc.), numbers, or double-quoted
+ strings. Everything is case sensitive.
+
+
+ Lines starting with a # are ignored.
+
+
+
+
+
+
BKI Commands
+
+
+
+
+ open tablename
+
+
+
+ Open the table called
+ tablename
+ for further manipulation.
+
+
+
+
+
+
+ close tablename
+
+
+
+ Close the open table called
+ class="parameter">tablename. It is an error if
+ tablename is not
+ already opened. If no
+ class="parameter">tablename is given, then the
+ currently open table is closed.
+
+
+
+
+
+
+ create tablename
+ (name1 =
+ type1 ,
+
name2 =
+ class="parameter">type2, ...)
+
+
+
+ Create a table named
+ class="parameter">tablename with the columns given
+ in parentheses.
+
+
+ The type is not necessarily the data
+ type that the column will have in the SQL environment; that is
+ determined by the pg_attribute system
+ catalog. The type here is essentially only used to allocate
+ storage. The following types are allowed: bool,
+ bytea, char (1 byte),
+ name, int2, int2vector,
+ int4, regproc, text,
+ oid, tid, xid,
+ cid, oidvector, smgr,
+ _int4 (array), _aclitem (array).
+ Array types can also be indicated by writing
+ [] after the name of the element type.
+
+
+
+ The table will only be created on disk, it will not
+ automatically be registered in the system catalogs and will
+ therefore not be accessible unless appropriate rows are
+ inserted in pg_class,
+ pg_attribute, etc.
+
+
+
+
+
+
+
+ insert OID = oid_value (value1 value2 ...)
+
+
+
+ Insert a new row into the open table using
+ class="parameter">value1,
+ class="parameter">value2, etc., for its column
+ values and
+ class="parameter">oid_value for its OID. If
+ oid_value is zero
+ (0) or the clause is ommitted, then the next available OID is
+ used.
+
+
+ NULL values can be specified using the special key word
+ _null_. Values containing spaces should be
+ double quoted.
+
+
+
+
+
+
+ declare
unique index
+ class="parameter">indexname on
+ class="parameter">tablename using
+ class="parameter">amname (
+ class="parameter">opclass1
+ class="parameter">name1 , ...)
+
+
+
+ Create an index named
+ class="parameter">indexname on the table named
+ tablename using the
+ amname access
+ method. The fields to index are called
+ class="parameter">name1,
+ class="parameter">name2 etc., and the operator
+ classes to use are
+ class="parameter">opclass1,
+ class="parameter">opclass2 etc., respectively.
+
+
+
+
+
+ build indices
+
+
+ Build the indices that have previously been declared.
+
+
+
+
+
+
+
+
+
Example
+
+ The following sequence of commands will create the
+ test_table table with the two columns
+ cola and colb of type
+ int4 and text, respectively, and insert
+ two rows into the table.
-create pg_opclass (opcname=name)
-open pg_opclass
-insert oid=421 (int_ops)
-print
-close pg_opclass
+create test_table (cola = int4, colb = text)
+open test_table
+insert OID=421 ( 1 "value1" )
+insert OID=422 ( 2 _null_ )
+close test_table
-
-
+
+
projects / postgresql.git / commitdiff