Capacity

Details

Fields in Table

as many as you want as long as the data still fits in a single block (64kb max)

Fields in an Index Key

as many as you want as long as 4 keys still fit in a single block (64kb max)

Indices in a Table

255

Open BLOBs in a Table

The maximum number of open blobs is only limited by the available memory constraints of the operating system or hardware.

Open Tables

The maximum number of open tables is only limited by the available memory constraints of the operating system or hardware.

Records in a Table

2^32

Records in a Transaction

The maximum number of records in a single transaction is only limited by the available memory constraints of the operating system or hardware.

Tables in a Database

limited only by the os file system

Size Of Database Names

The maximum size of a database name is 60 bytes.

Size Of Field Constraint

unlimited

Size Of Field Descriptions

unlimited

Size Of Field Names

unlimited

Size Of Index Names

unlimited

Size Of Physical Table Files

2^32 blocks, possible block sizes are 4, 8, 16, 32, 64kb; file size may be limited by file system used

Size Of Table Descriptions

unlimited

Size Of Table Names

limited by the used file system

Size of BLOB Blocks

blobs are stored in segments with 4 byte granularity

Size of BLOB Fields

The maximum length of a BLOB field is 4 gigabytes. Some access methods (e.g. Tdataset in D6 and older) are limited to 2 gb

Size of In-Memory Tables

The maximum size of an in-memory table is only limited by the available memory constraints of the operating system or hardware.

Size of Index Keys

The maximum size of an index key is 1/4 of the block size minus some bytes for per block overhead. The exact index key size depends on the key engine used.

Size of Index Pages

same as "physical table files"

Size of Records

The maximum record size is a bit under 64 kilobytes.

Size of String Fields

The maximum length of a string field is only limited by total record size. Some access methods may further limit the maximum string field size

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