Foxpro Limitations questions

Question : Foxpro Limitations questions

I’m looking for site or information for limitations in foxpro.

What im looking for are things like
Maximum string size in variable
Maximum Fields in table
Maximum Table size
Maximum Select (no of fields here) from ….
Maximum INLIST(….)
Maximum Records in a table
Maximum length of variable name in fields
Maximum length variable name
etc.
you get the idea. does anyone know?
There’s an info for this in MsSQL2000. I dunno if theres for fxpro.


Solution: Foxpro Limitations questions

For FoxPro 2.6 and then for Visual FoxPro 7.0

====================================================================================================================================
Fox Pro 2.6
Standard              Extended
&&&&&&&&            &&&&&&&&

Database and Index Files
&&&&&&&&&&&&&&&&&&&&&&&&

Max # of records per database*
1 billion            1 billion

Max # of chars per record
65,500                  65,500

Max # of fields per record
255                        255

Max # of open DBFs
25                        225

Max # of chars per field
254                        254

Max # of chars per index key (IDX)
100                        100

Max # of chars per index key (CDX)
240                        240

Max # of open index files per database**
unlimited            unlimited

Max # of open index files in all work areas**
unlimited            unlimited

Max # of relations
unlimited

Max length of relational expressions
unlimited

Field Characteristics
&&&&&&&&&&&&&&&&&&&&&

Max size of character fields
254                        254

Max size of numeric fields
20                        20

Max # of chars in field names
10                        10

Digits of precision in numeric computations
16                        16

Memory Variables and Arrays
&&&&&&&&&&&&&&&&&&&&&&&&&&&

Default # of memory variables
1024                  1024

Max # of memory variables
3,600                  65,000

Max # of arrays
3,600                  65,000

Max # of elements per array
3,600                  65,000

Program and Procedure Files
&&&&&&&&&&&&&&&&&&&&&&&&&&&

Max # of lines in source program files
unlimited            unlimited

Max size of a single compiled PROCEDURE or FUNCTION
64K                        64K

NOTE: A program or application can contain an unlimited number of program modules.

Max # of procedures per file
unlimited            unlimited

Max # of nested DO calls
32                        32

Max # of READ nesting levels
5                        5

Max # of nested structured programming commands
64                        64

Report Writer Capacities
&&&&&&&&&&&&&&&&&&&&&&&&

Max # of objects in a report definition
unlimited**            unlimited**

Max # of lines in a report definition
255                        255

Max # of grouping levels
20                        20

Window Support
&&&&&&&&&&&&&&
Max # of open windows
unlimited**            unlimited**

Max # of open Browse windows
25                        225

Miscellaneous Capacities
&&&&&&&&&&&&&&&&&&&&&&&&

Max # of chars per string
64K                        2 gigabytes

Max # of chars per command line
2,048                  2,048

Max # of chars per macro subst.
2,048                  2,048

Max # of open files
99                        MS-DOS limit

Max # of keystrokes per keyboard macro
1,024                  1,024

Max fields that can be selected by a SQL SELECT statement — in the projection list (same as the maximum fields per record in a database)
255                        255

Color Support
&&&&&&&&&&&&&

Number of color schemes per color set
24                        24

Max # of color sets
unlimited            unlimited

Number of colors per scheme
10                        10

Schemes available for user definition
8                        8

*      The actual file size (in bytes) cannot exceed 2 gigabytes for single-user or exclusively opened multi-user .DBF files.  Shared .DBF files with no indexes or .IDX indexes cannot exceed 1 gigabyte.  Shared .DBF files with structural .CDX indexes cannot exceed 2 gigabytes.

**      Limited by memory and available MS-DOS file handles.  Each .CDX file uses only 1 file handle.  The number of MS-DOS file handles is determined by the CONFIG.SYS FILES parameter.

====================================================================================================================================

And For Visual FoxPro 7.0

Some capacities may be limited by available memory.

Category Feature Number

Table and Index Files

Maximum # of records per table file 1 billion
Maximum size of a table file 2 gigabytes
Maximum # of characters per record 65,500
Maximum # of fields per record(1) 255
Maximum # of tables open at one time(2) 255
Maximum # of characters per table field 254
Maximum # of bytes per index key in a non-compact index(3) 100
Maximum # of bytes per index key in a compact index(3) 240
Maximum # of open index files per table(2) unlimited
Maximum # of open indexes in all work areas(2) unlimited
Maximum # of relations unlimited
Maximum length of relational expressions unlimited

Field Characteristics

Maximum size of character fields 254
Maximum size of numeric (and float) fields 20
Maximum number of characters in field names in a free table 10
Maximum number of characters in field names in a table contained in a database 128
Minimum value of an integer -2,147,483,647
Maximum value of an integer 2,147,483,647
Digits of precision in numeric computations
Visual FoxPro can handle numbers up to 9007199254740992 (2^53) in exact computations. 16
64 bits = 8 bytes
Largest number = 10 ^ 308    =   2 ^ 1023 -> 10 bits per
exponent + 1 for exp sign plus 1 for the number’s sign => 12 bits.
Leaving 52 bits for the mantissa + 1 for implied normalized bit -> 53 bits
LOG10(2^53) = 15.95 decimal digits accuracy.

Variables and Arrays

Default # of variables 1,024
Maximum # of variables 65,000
Maximum # of arrays 65,000
Maximum # of elements per array 65,000

Program and Procedure Files

Maximum # of lines in source program files unlimited
Maximum size of compiled program
modules(4) 64K
Maximum # of procedures per file unlimited
Maximum # of nested DO calls 128
Maximum # of READ nesting levels 5
Maximum # of nested structured programming commands  384
Maximum # of passed parameters 27
Maximum # of transactions 5

Report Designer Capacities

Maximum # of objects in a report definition(2) unlimited
Maximum length of a report definition 20 inches
Maximum # of grouping levels 128
Maximum length of character report variables 255

Other Capacities

Maximum # of open windows (all types)(2) unlimited
Maximum # of open Browse windows 255
Maximum # of characters per character string or memory variable 16,777,184
Maximum # of characters per command line 8,192
Maximum # of characters per label control on a report 252
Maximum # of characters per macro substituted line 8,192
Maximum # of open files  System limit
Maximum keystrokes in keyboard macro  1,024
Maximum fields that can be selected by a SQL SELECT statement 255
Maximum length of a string literal 255

1. If one or more fields allow null values, the limit is reduced by one to 254 fields.
2. Limited by memory and available file handles. .cdx files use only one file handle.
3. If the collating sequence is set to MACHINE, each character uses one byte. If the collating sequence is not set to MACHINE, each character uses two bytes. If the indexed field supports null values, one additional byte is used in the index key. Note that non-machine indexes are always compact.
4. A program module is one procedure. A program or application can contain an unlimited number of program modules.