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Quasar SQL Syntax Page 1 of 34
Quasar SQL For Windows
Release 2.0 - November 1991
Quasar SQL SYNTAX
Copyright (c) 1991 by Stellar Industries
All Rights Reserved
Summary
This manual is divided into nine sections:
Overview This section describes, in general terms, what
SQL is and the notation used in this document.
Statements This section includes a description of the
syntax of all SQL Statements which your program
can use.
Data Types This section includes a description of all data
types recognized by SQL.
Operators This section includes a description of all
arithmetic operators used with SQL.
Built-in Functions This section includes a description of all
built-in functions used with SQL.
Expressions This section includes a description of the
syntax of expressions used with SQL.
Search Condition This section includes a description of the
syntax used to select specific data elements.
System Catalog This section includes a description of the
tables used by the Quasar Database Administrator
to keep track of the database.
Glossary This section defines specialized terms used in
this document.
Summary
Quasar SQL Syntax Page 2 of 34
Overview
General Information
Structured Query Language (SQL) is the database
management language declared by the American
National Standards Institute (ANSI) as a standard.
SQL is the lingua franca of the computer database
world. SQL is used on mainframes, minicomputers and
PCs.
Notational Conventions
While uppercase is used throughout this document to
indicate SQL keywords (COMMIT, SELECT, etc), in
actuality the Quasar Database Administrator will
accept keywords in either upper or lowercase. The
keyword 'COMMIT' may be spelled 'commit', 'Commit',
'COMMIT', etc.
The names of users, tables, indices and columns, and
the content of character fields are, however, case
sensitive. If you used some combination of upper
and lower case to create them, you have to use the
same combination to access them. All system names
were created using upper case only.
Optional elements are indicated by enclosing them
within square brackets as in [option]. When a
choice may be made among a list of possible optional
elements, individual selections are separated by
vertical bars as in [option1 | option2 | option3].
When a pattern may be repeated, an ellipsis follows
the pattern as in "ColumnName1 [, ColumnName2] ...".
This example implies a list of one or more column
names separated by commas.
Overview
Quasar SQL Syntax Page 3 of 34
Statements
SQL is based on various uses of the following statements:
COMMIT WORK Instructs the database administrator to make
all changes to the database by the current
transaction permanent.
CREATE INDEX Creates an index on a database table.
CREATE TABLE Creates a database table.
DELETE Deletes records from a database table.
DROP INDEX Deletes an index from a database table.
DROP TABLE Deletes a database table.
INSERT Creates records in a database table.
ROLLBACK WORK Instructs the database administrator to forget
all changes made to the database by the current
transaction.
SELECT Retrieves data from database tables.
UPDATE Modifies the content of records within database
tables.
Statements
Quasar SQL Syntax Page 4 of 34
Statement: COMMIT WORK
Syntax COMMIT WORK;
Changes made to the database are not made
permanent until this statement is executed.
Should the current user execute a ROLLBACK WORK
or unexpectedly log off, all changes made by
the user since logging in or executing a COMMIT
WORK (whichever occurred most recently) will
vanish.
During database recovery only committed
transactions are restored.
Comments As queries are executed within a transaction
and records are created, read, updated or
deleted; the database applies various kinds of
locks on the applicable records. These locks
are released when the transaction is committed
or rolled back. In order to minimize the
conflict between transactions, be sure to
minimize the amount of time these locks are in
place by issuing a COMMIT WORK or ROLLBACK WORK
whenever possible.
Committing a transaction automatically starts a
new transaction. COMMIT WORK is very fast
since the changes have already been made, they
are merely flagged as permanent.
Statements: COMMIT WORK
Quasar SQL Syntax Page 5 of 34
Statement: CREATE INDEX
Syntax CREATE [UNIQUE] INDEX
[CreatorName.]IndexName
ON [UserName.]TableName (
ColumnName1 [ASC | DESC][,
ColumnName2 [ASC | DESC]]
...
);
This statement creates the index IndexName on
the table TableName. While indices are never
referenced explicitly in SQL (other than
creating and dropping them), they are used
extensively by the Quasar Database Administrator
to maximize system performance.
Phrase Description
CREATE [UNIQUE] INDEX
Specify UNIQUE if you wish key
values to be distinguishable,
one from another, across the
entire table upon which the
index is constructed. If an
attempt is made to create a
record in the table which
violates this unique constraint,
an error condition will arise.
[CreatorName.]IndexName
IndexName becomes the name of
the newly created index.
Specify CreatorName if you wish
the index to belong to a user
different from the current user.
ON [UserName.]TableName
TableName identifies the table
upon which the index is to be
constructed. Specify UserName
if the table belongs to a user
different from the current user.
ColumnName1 [ASC | DESC]
ColumnName identifies a column
in the table to be included in
the index key. Specify ASC for
ascending and DESC for
Statements: CREATE INDEX
Quasar SQL Syntax Page 6 of 34
descending. ASC is default. We
recommend against the use of
DESC, it is included in order to
conform to the ANSI standard.
[, ColumnName2 [ASC | DESC]] ...
Additional columns may be
included within the index key by
creating a list of columns
separated by commas. The index
key will be constructed in the
order in which columns appear in
this list.
Comments While indices may be created at anytime, we
recommend that you create indices immediately
after you create their base table; otherwise,
CREATE INDEX has to read and rewrite all data
which is already in the table.
The presence of suitable indices may greatly
enhance system performance. Indices do,
however, cause a moderate increase in the
amount of time it takes to write a record to
the table upon which the index is constructed.
The database user should add indices
judiciously.
ColumnName, CreatorName, IndexName, TableName
and UserName are limited to 32 characters.
Statements: CREATE INDEX
Quasar SQL Syntax Page 7 of 34
Statement: CREATE TABLE
Syntax CREATE TABLE [UserName.]TableName (
ColumnName1 DataType1 [NOT NULL [UNIQUE]][,
ColumnName2 DataType2 [NOT NULL [UNIQUE]]]
...
[UNIQUE (ColumnNameA[, ColumnNameB] ... )][,
UNIQUE (ColumnNameA[, ColumnNameB] ... )]
...
);
This statement creates the table TableName with
the columns as specified.
Phrase Description
CREATE TABLE [UserName.]TableName
TableName becomes the name of
the newly created table.
Specify UserName if you wish the
table to belong to a user
different from the current user.
ColumnName1 DataType1 [NOT NULL [UNIQUE]]
ColumnName identifies a column
to be included in the table.
DataType indicates the data type
of the column.
When a column is specified as
NOT NULL, any attempt to insert
or update a record which would
result in a NULL value in this
column will cause an error
condition to arise.
When a column is specified as
UNIQUE, an UNIQUE index is
automatically created for that
column. This index will insure
that all values for that column
are distinguishable, one from
another, across the entire
table. Any attempt to insert or
update a record which violates
this unique constraint will
cause an error condition to
arise.
[, ColumnName2 DataType2 [NOT NULL UNIQUE]]]
...
Statements: CREATE TABLE
Quasar SQL Syntax Page 8 of 34
Additional columns may be
included within the table by
creating a list of column
definitions separated by commas.
[UNIQUE (ColumnNameA[, ColumnNameB] ... )]
The combination of ColumnNameA,
ColumnNameB, ... are to be
unique across all records in the
table.
An UNIQUE index which includes
the named columns is
automatically created. This
index will insure that key
values for these columns are
distinguishable, one from
another, across the entire
table. Any attempt to insert or
update a record which violates
this unique constraint will
cause an error condition to
arise.
[, UNIQUE (ColumnNameN[, ColumnNameO] ... )]
Additional unique constraints
may be added by creating a list
of unique constraint definitions
separated by commas. Each
unique constraint is maintained
by a separate UNIQUE index.
Comments ColumnName, TableName and UserName are limited
to 32 characters.
Statements: CREATE TABLE
Quasar SQL Syntax Page 9 of 34
Statement: DELETE
Syntax DELETE FROM [UserName.]TableName
[WHERE SearchCondition];
This statement deletes records from the table
TableName. SearchCondition specifies which
records are to be deleted.
Phrase Description
DELETE FROM [UserName.]TableName
TableName is the name of the
table containing the records to
be deleted. Specify UserName if
the table belongs to a user
different from the current user.
WHERE SearchCondition
SearchCondition specifies which
records are to be deleted.
Comments TableName and UserName are limited to 32
characters.
Statements: DELETE
Quasar SQL Syntax Page 10 of 34
Statement: DROP INDEX
Syntax DROP INDEX [CreatorName.]IndexName
ON [UserName.]TableName;
This statement deletes the index IndexName on
the table TableName.
Phrase Description
DROP INDEX [CreatorName.]IndexName
IndexName is the name of the
index to be deleted. Specify
CreatorName if the index belongs
to a user different from the
current user.
ON [UserName.]TableName
TableName identifies the table
upon which the index exists.
Specify UserName if the table
belongs to a user different from
the current user.
Comments While indices may be dropped at anytime,
dropping an index on a table causes the entire
table to be rebuilt.
When a table is deleted, all indices associated
with that table are automatically dropped.
CreatorName, IndexName, TableName and UserName
are limited to 32 characters
Statements: DROP INDEX
Quasar SQL Syntax Page 11 of 34
Statement: DROP TABLE
Syntax DROP TABLE [UserName.]TableName;
This statement deletes the table TableName.
Phrase Description
DROP TABLE [UserName.]TableName
TableName is the name of the
table to be deleted. Specify
UserName if the table belongs to
a user different from the
current user.
Comments All indices associated with the table are
automatically dropped.
TableName and UserName are limited to 32
characters
Statements: DROP TABLE
Quasar SQL Syntax Page 12 of 34
Statement: INSERT
Syntax INSERT INTO [UserName.]TableName
[(ColumnName1[, ColumnName2] ... )]
VALUES (Value1[, Value2] ... );
-- or --
Syntax INSERT INTO [UserName.]TableName
[(ColumnName1[, ColumnName2] ... )]
SelectStatement;
This statement inserts records into the table
TableName.
Phrase Description
INSERT INTO [UserName.]TableName
TableName is the name of the
table into which records are to
be inserted. Specify UserName
if the table belongs to a user
different from the current user.
(ColumnName1[, ColumnName2] ... )
Identifies columns into which
data is to be deposited. If any
columns exist in the table which
are not listed, they are set to
the NULL value. A column name
may not be repeated. Column
names do not have to be in the
same order as they are in the
table itself.
VALUES (Value1[, Value2] ... )
Specifies the values to be
deposited in the record. If a
list of columns was supplied,
there must be a match between
the number of column names in
the list and the number of
values supplied. If a list of
columns was not supplied, there
must be a match between the
total number of columns in the
table and the number of values
supplied.
Statements: INSERT
Quasar SQL Syntax Page 13 of 34
The data type of the value must
be compatible with the data type
of the column into which it is
to be deposited. When the
column allows the NULL value,
the value may be 'NULL'.
SelectStatement
The SelectStatement generates a
set of records to be inserted.
If a list of columns was
supplied, there must be a match
between the number of column
names in the list and the number
of columns generated by the
SelectStatement. If a list of
columns was not supplied, there
must be a match between the
total number of columns in the
table and the number of columns
generated by the
SelectStatement.
The data types of the columns
generated by the SelectStatement
must be compatible with the data
types of the columns into which
they are to be deposited.
Comments ColumnName, TableName and UserName are limited
to 32 characters.
Statements: INSERT
Quasar SQL Syntax Page 14 of 34
Statement: ROLLBACK WORK
Syntax ROLLBACK WORK;
Changes made to the database are not made
permanent until a COMMIT WORK statement is
executed. ROLLBACK WORK instructs the database
to purge all changes to the database by the
current user since logging in or executing a
COMMIT WORK (whichever occurred most recently).
Comments As queries are executed within a transaction
and records are created, read, updated or
deleted; the database applies various kinds of
locks on the applicable records. These locks
are released when the transaction is committed
or rolled back. In order to minimize the
conflict between transactions, be sure to
minimize the amount of time these locks are in
place by issuing a COMMIT WORK or ROLLBACK WORK
whenever possible.
Rolling a transaction back automatically starts
a new transaction. ROLLBACK WORK may take some
time while the database administrator purges
updates.
Statements: ROLLBACK WORK
Quasar SQL Syntax Page 15 of 34
Statement: SELECT
Syntax SELECT [ALL | DISTINCT]
Expression1[, Expression2] ...
FROM [UserName1.]TableName1 [CorrelationName1][,
[UserName2.]TableName2 [CorrelationName2]]
...
[WHERE SearchCondition]
[GROUP BY ColumnSpecification1[,
ColumnSpecification2]
...
[HAVING SearchCondition]]
[ORDER BY ColumnSpecificationA [ASC | DESC][,
ColumnSpecificationB [ASC | DESC]]
...];
This statement generates a result table. There
is one column in the result table for each
Expression in the expression list of the SELECT
statement. The values deposited in the columns
of the result table are generated by evaluating
the corresponding Expression.
Phrase Description
SELECT [ALL | DISTINCT]
ALL is default. DISTINCT
insures that all records in the
result table are
distinguishable, one from
another. When DISTINCT is
specified, duplicate records are
eliminated from the result
table.
Expression1[, Expression2]
This list specifies the values
to be inserted into the columns
of the result table. The data
types of the columns of the
result table are determined by
the data types of the values
resulting from the expressions
in this list.
You may substitute a single '*'
in place of the list of
expressions. '*' implies a list
of all columns of all tables
identified in the FROM clause.
Statements: SELECT
Quasar SQL Syntax Page 16 of 34
You may not use '*' if you use
the GROUP BY clause.
FROM [UserName1.]TableName1 [CorrelationName1]
TableName is the name of the
table from which records are to
be read. Specify UserName if
the table belongs to a user
different from the current user.
CorrelationName is effectively
an alias for the TableName which
it follows.
[, [UserName2.]TableName2 [CorrelationName2]]
...
Additional tables may be
included by creating a list of
tables separated by commas.
This effectively creates a
Cartesian product of all the
tables in the list.
WHERE SearchCondition
SearchCondition specifies which
records are to be read.
GROUP BY ColumnSpecification1
Rearranges the table(s)
identified by the FROM clause
into groups such that within any
one group all rows have the same
value for the GROUP BY
column(s). The SELECT clause is
then applied to these groups.
Each group generates a single
record in the result table.
Please refer to a text book for
a description of the "grouped
table". "Grouped tables" are
fully supported by the Quasar
Database Administrator.
[, ColumnSpecification2] ...
Additional columns may be
included within the GROUP BY
clause by creating a list of
columns separated by commas.
Statements: SELECT
Quasar SQL Syntax Page 17 of 34
Please refer to a text book for
a description of the "grouped
table". "Grouped tables" are
fully supported by the Quasar
Database Administrator.
HAVING SearchCondition
Specifies a restriction on the
grouped table resulting from the
GROUP BY clause by eliminating
groups not meeting the
SearchCondition.
Please refer to a text book for
a description of the "grouped
table". "Grouped tables" are
fully supported by the Quasar
Database Administrator.
ORDER BY ColumnSpecificationA [ASC | DESC]
Records in the result table will
be sorted on the basis of the
data in the columns specified by
the ORDER BY clause. Specify
ASC for ascending and DESC for
descending. ASC is default.
ColumnSpecification must
identify one of the Expressions
within the list of expressions
of the SELECT STATEMENT. An
integer may be used in place of
the ColumnSpecification; when an
integer is used it identifies
which column in the result table
is to be used to determine the
order.
[, ColumnSpecificationB [ASC | DESC]] ...
Additional ordering
ColumnSpecifications (or
integers) may be included within
the ORDER BY clause by creating
a list of columns (or integers)
separated by commas.
Comments CorrelationName, TableName and UserName are
limited to 32 characters.
Statements: SELECT
Quasar SQL Syntax Page 18 of 34
Statement: UPDATE
Syntax UPDATE [UserName.]TableName
SET ColumnName1 = Expression1[,
ColumnName2 = Expression2]
...
[WHERE SearchCondition];
This statement modifies records in the table
TableName. SearchCondition specifies which
records are to be modified.
Phrase Description
UPDATE [UserName.]TableName
TableName is the name of the
table in which records are to be
modified. Specify UserName if
the table belongs to a user
different from the current user.
SET ColumnName1 = Expression1
Expression is evaluated and the
result placed in the column
identified by ColumnName.
Columns not specifically
identified are left unaffected.
[, ColumnName2 = Expression2] ...
Additional columns may be
modified by creating a list of
ColumnNames and Expressions
separated by commas. A column
name may not be repeated.
[WHERE SearchCondition]
SearchCondition specifies which
records are to be modified.
Comments ColumnName, TableName and UserName are limited
to 32 characters.
Statements: UPDATE
Quasar SQL Syntax Page 19 of 34
Data Types
Data types are organized into three basic categories:
Approximate Numeric This type is typically referred to as
floating point.
Exact Numeric This type is typically referred to as fixed
point.
Character String This type is used to store text.
Data Types
Quasar SQL Syntax Page 20 of 34
Data Types: Approximate Numeric
This type is typically referred to as floating point.
Data type Description
FLOAT Floating point number with magnitude ranging
from approximately 1.7976931348623158e+308 to
2.2250738585072014e-308.
FLOAT(p) Floating point number with p significant
digits, with magnitude ranging from
approximately 1.7976931348623158e+308 to
2.2250738585072014e-308.
REAL Floating point number with magnitude ranging
from approximately 1.7976931348623158e+308 to
2.2250738585072014e-308.
DOUBLE PRECISION Floating point number with magnitude ranging
from approximately 1.7976931348623158e+308 to
2.2250738585072014e-308.
Data Types: Approximate Numeric
Quasar SQL Syntax Page 21 of 34
Data Types: Exact Numeric
This type is typically referred to as fixed point.
Data type Description
DEC Signed decimal number with up to 19 digits of
which 0 appear to the right of the decimal
point.
DEC(p) Signed decimal number with up to p digits of
which 0 appear to the right of the decimal
point; 1 <= p <= 19.
DEC(p, s) Signed decimal number with up to p digits of
which s appear to the right of the decimal
point; 1 <= p <= 19 and 0 <= s <= p.
DECIMAL Signed decimal number with up to 19 digits of
which 0 appear to the right of the decimal
point.
DECIMAL(p) Signed decimal number with up to p digits of
which 0 appear to the right of the decimal
point; 1 <= p <= 19.
DECIMAL(p, s) Signed decimal number with up to p digits of
which s appear to the right of the decimal
point; 1 <= p <= 19 and 0 <= s <= p.
INT Whole number ranging from -2147483647 to
2147483647.
INTEGER Whole number ranging from -2147483647 to
2147483647.
NUMERIC Signed decimal number with up to 19 digits of
which 0 appear to the right of the decimal
point.
NUMERIC(p) Signed decimal number with up to p digits of
which 0 appear to the right of the decimal
point; 1 <= p <= 19.
NUMERIC(p, s) Signed decimal number with up to p digits of
which s appear to the right of the decimal
point; 1 <= p <= 19 and 0 <= s <= p.
SMALLINT Whole number ranging from -2147483647 to
2147483647.
Data Types: Exact Numeric
Quasar SQL Syntax Page 22 of 34
Data Types: Character String
This type is used to store text.
Data type Description
CHAR Character data, length assumed to be 1.
CHAR(n) Character data, length specified by n where 1
<= n <= 2047.
CHARACTER Character data, length assumed to be 1.
CHARACTER(n) Character data, length specified by n where 1
<= n <= 2047.
VARCHAR Character data, variable length where maximum
length is 2047.
VARCHAR(n) Character data, variable length where maximum
length is specified by n where 1 <= n <= 2047.
Data Types: Character String
Quasar SQL Syntax Page 23 of 34
Operators
The arithmetic operators have their usual meanings:
+ The value on the right is added to the value on
the left.
- The value on the right is subtracted from the
value on the left.
* The value on the right is multiplied by the
value on the left.
/ The value on the left is divided by the value
on the right.
Operators
Quasar SQL Syntax Page 24 of 34
Built-in functions
Built-in functions act on several rows in a table together.
Built-in functions may not be nested. SQL supports the
following built-in functions:
AVG(Expression) For each record selected, Expression
is analyzed and a value obtained.
AVG returns the average of these
values. Only values which are not
NULL are included.
COUNT(DISTINCT Expression) For each record selected,
Expression is analyzed and a value
obtained. COUNT(DISTINCT) returns
the number of these values which are
distinguishable, one from another.
Only values which are not NULL are
included.
COUNT(*) COUNT(*) returns the number of
records selected.
MAX(Expression) For each record selected, Expression
is analyzed and a value obtained.
MAX returns the maximum of these
values. Only values which are not
NULL are included.
MIN(Expression) For each record selected, Expression
is analyzed and a value obtained.
MIN returns the minimum of these
values. Only values which are not
NULL are included.
SUM(Expression) For each record selected, Expression
is analyzed and a value obtained.
SUM returns the sum of these values.
Only values which are not NULL are
included.
Built-in functions
Quasar SQL Syntax Page 25 of 34
Expressions
Expressions can be:
A column name
A constant or literal value
A built-in function
An arithmetic combination of expressions
Constants can be:
Integer (for example: 100, -5, +127)
Decimal (for example: 100.0, -.001, 1., +1.5)
Floating point (for example: 1E10, -2E-7, +3.14159E0)
Character string (for example: 'SMITH' '-@k9-22', '-1',
'Quasar')
Order of execution:
Arithmetic expressions are evaluated before comparisons
and logical operations.
Arithmetic expressions are evaluated left to right except
that multiplication and division are performed before
addition and subtraction. Parentheses can be used to
control the order of evaluation.
Expressions
Quasar SQL Syntax Page 26 of 34
Search Conditions
A search condition can be a simple condition or a logical
combination of conditions. If the value of any expression is
NULL then the condition evaluates to UNKNOWN:
Simple conditions:
Expression1 = Expression2
Evaluates to TRUE if and only if Expression1
has a value equal to that of Expression2,
otherwise the condition evaluates to FALSE.
Expression1 < Expression2
Evaluates to TRUE if and only if Expression1
has a value less than that of Expression2,
otherwise the condition evaluates to FALSE.
Expression1 <= Expression2
Evaluates to TRUE if and only if Expression1
has a value less than or equal to that of
Expression2, otherwise the condition evaluates
to FALSE.
Expression1 > Expression2
Evaluates to TRUE if and only if Expression1
has a value greater than that of Expression2,
otherwise the condition evaluates to FALSE.
Expression1 >= Expression2
Evaluates to TRUE if and only if Expression1
has a value greater than or equal to that of
Expression2, otherwise the condition evaluates
to FALSE.
Expression1 <> Expression2
Evaluates to TRUE if and only if Expression1
has a value which is not equal to that of
Expression2, otherwise the condition evaluates
to FALSE.
Expression1 [NOT] BETWEEN Expression2 AND Expression3
Same as [NOT] ((Expression2 <= Expression1) AND
(Expression1 <= Expression3).
Expression1 [NOT] IN (Value1[, Value2] ...)
Search Conditions
Quasar SQL Syntax Page 27 of 34
Same as [NOT] ((Expression1 = Value1)[ OR
(Expression1 = Value2)] ... .
Expression1 [NOT] IN (Subquery)
TRUE if Expression1 is [not] equal to any value
returned by Subquery.
ColumnName [NOT] LIKE Pattern
Only available for character types: [not] TRUE
if the string in the specified column matches
Pattern. In Pattern, '_' matches any single
character, '%' matches any character sequence.
ColumnName IS [NOT] NULL
True if the value of ColumnName is [not] NULL.
[NOT] EXISTS (Subquery)
[Not] TRUE if Subquery returns at least one
record.
Expression1 [NOT] IN (Subquery)
[Not] TRUE if Subquery returns at least one
value which is equal to Expression1.
Expression1 = [ANY | ALL | SOME] (Subquery)
Expression1 < [ANY | ALL | SOME] (Subquery)
Expression1 <= [ANY | ALL | SOME] (Subquery)
Expression1 > [ANY | ALL | SOME] (Subquery)
Expression1 >= [ANY | ALL | SOME] (Subquery)
Expression1 <> [ANY | ALL | SOME] (Subquery)
Please refer to a text book for a description
of the "quantified" predicate. While
supported, we recommend against its use.
Logical combination of conditions:
NOT Condition
Evaluates to TRUE if and only if Condition is
FALSE. Evaluates to FALSE if and only if
Condition is TRUE.
Condition1 AND Condition2
Evaluates to TRUE if and only if both
Condition1 and Condition2 are TRUE.
Condition1 OR Condition2
Search Conditions
Quasar SQL Syntax Page 28 of 34
Evaluates to TRUE if either Condition1 or
Condition2 is TRUE or both are TRUE. Evaluates
to TRUE even if one condition is UNKNOWN.
Search Conditions
Quasar SQL Syntax Page 29 of 34
System Catalog
The system catalog is composed of four tables: SYSTEM.COLUMNS,
SYSTEM.INDICES, SYSTEM.TABLES and SYSTEM.USERS. All these
tables belong to the user "SYSTEM". These tables are
maintained by the Quasar Database Administrator.
Unless otherwise indicated, you must not modify the
SYSTEM.COLUMNS, SYSTEM.INDICES, SYSTEM.TABLES and SYSTEM.USERS
tables.
COLUMNS This table contains information about all
columns of all tables in the database.
INDICES This table contains information about all
indices in the database. When more than one
column is included in an index, there is a
separate record for each column included.
TABLES This table contains information about all
tables in the database.
USERS This table contains information about all users
known to the database.
System Catalog
Quasar SQL Syntax Page 30 of 34
System Catalog: SYSTEM.COLUMNS
This table contains information about all columns of all
tables in the database. You may only modify the REMARK field
of records in this table.
Column Type/Description
SEQUENCE_NUMBER SMALLINT Indicates the position of the column
within the table.
LENGTH SMALLINT Indicates the length of character
strings or the precision of numeric values.
SCALE SMALLINT Indicates the scale of numeric values.
DATA_TYPE VARCHAR(32) Indicates data type.
NOT_NULL CHARACTER(5) Indicates whether NULL values are
allowed. TRUE indicates NULL is not allowed.
USER_NAME VARCHAR(32) Indicates the user name of the
owner of the table.
TABLE_NAME VARCHAR(32) Indicates the name of the table.
COLUMN_NAME VARCHAR(32) Indicates the name of the column.
REMARK VARCHAR(128) A comment.
System Catalog: SYSTEM.COLUMNS
Quasar SQL Syntax Page 31 of 34
System Catalog: SYSTEM.INDICES
This table contains information about all indices in the
database. When more than one column is included in an index,
there is a separate record for each column included. You may
only modify the REMARK field of records in this table.
The INDEX_NAME of indices created to enforce unique
constraints have a '~' as their first character.
Column Description
USER_NAME VARCHAR(32) Indicates the user name of the
owner of the table upon which the index is
constructed.
TABLE_NAME VARCHAR(32) Indicates the name of the table
upon which the index is constructed.
INDEX_NAME VARCHAR(32) Indicates the name of the index.
SEGMENT_NUMBER SMALLINT Indicates the position of the column
within the index key.
NUMBER_OF_SEGMENTS SMALLINT Indicates the number of columns
included in the index key.
DESCENDING CHARACTER(5) Indicates whether the index is
marked as ascending or descending. ASC
indicates ascending while DESC indicates
descending.
UNIQUE CHARACTER(5) Indicates whether duplicate values
are allowed. TRUE indicates all values must be
distinguishable, one from another. FALSE
indicates duplicate values are allowed.
CREATOR_NAME VARCHAR(32) Indicates the user name of the
creator of the index.
COLUMN_NAME VARCHAR(32) Indicates the name of the column
which makes up this segment of the index key.
REMARK VARCHAR(128) A comment.
System Catalog: SYSTEM.INDICES
Quasar SQL Syntax Page 32 of 34
System Catalog: SYSTEM.TABLES
This table contains information about all tables in the
database. You may only modify the REMARK field of records in
this table.
The TABLE_NAME of temporary tables used during the execution
of a query have a '~' as their first character.
Column Description
TABLE_ID SMALLINT Used internally to identify the MSDOS
files used in the table.
NUMBER_OF_COLUMNS SMALLINT Indicates the number of columns in
the table.
ISAM_CONTROL_BLOCK BINARY Used internally to save the ISAM
control block for the table.
USER_NAME Indicates the name of the user who owns the
table.
TABLE_NAME VARCHAR(32) Indicates the name of the table.
REMARK VARCHAR(128) A comment.
System Catalog: SYSTEM.TABLES
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System Catalog: SYSTEM.USERS
This table contains information about all users known to the
database.
You may manage user access by modifying the SYSTEM.USERS
table. Use Caution: deleting all user records will
permanently lock you out of the database. Do not delete the
user "SYSTEM".
Column Description
USER_NAME VARCHAR(32) Indicates a user name.
USER_PASSWORD VARCHAR(32) Indicates a user password.
REMARK VARCHAR(128) A comment.
System Catalog: SYSTEM.USERS
Quasar SQL Syntax Page 34 of 34
Glossary
current user The current user is the user who
logged into the database to execute
the query.
key A key is the set of columns within a
table used to construct an index on
that table.
key value The database administrator creates a
key value by concatenating the values
of all columns defined in an index.
The columns are concatenated in the
order in which they were specified
when the index was created.
result table All SELECT queries generate a table
containing the chosen records. This
is called the result table. Its
contents are made available to you
one at a time through one of the
Quasar SQL API fetch Statements.
transaction journal A transaction journal is a pair of
files ('or_log.dat' and 'or_log.idx')
written by the database manager. The
transaction journal contains a record
of every event which caused a change
to the database.
Glossary
