摘自firebird官方资料，ahe对关键地方简单翻译，若有谬误，请参考原文。
数据库限制
| 项目 | Firebird 2.x | Firebird 1.5.x |
| 数据库最大尺寸 | 使用多个库文件存储条件下，理论上不限制数据库尺寸，目前已知的最大FB数据库为980 GB | 使用多个库文件存储条件下 32 TB |
| 单个数据库文件最大尺寸 | 多数操作系统下支持TB级库文件; 但受文件系统限制(比如某些操作系统下限制单个文件最大4 GB 或 2 GB) | Same |
| 数据库文件最大个数 | 64,535 | Same |
| 最大表数量 | 64,535 | Same |
| 单表最大尺寸 | ~32 TB | ~36 GB |
| 外链表最大尺寸 | 2 GB | Same |
| 单表最大记录数 | > 16 亿(超出此记录数尚未测试) | ~4 Billion |
| 注意: 此1 亿实际是 1024的三次方 | ||
| 最大记录尺寸 | 65,536 字节(64 KB) | Same |
| 数据库分页最大尺寸 | 16 KB | Same |
| NOTE: Page size (PAGE_SIZE) can be 1024, 2048, 4096, 8192 or 16384. Size 1024 is not recommended. | ||
| 每表最大字段数 | 取决于字段类型. (例如: 16,384 INTEGER (4-字节) 每行)（译者注：受64K最大记录尺寸限制） | |
| NOTE: 8-byte ID is stored for each BLOB or ARRAY reference; size of BLOB or ARRAY data is not counted in row size. | ||
| 每表最大索引树 | 65,535 | Same |
| Maximum size (total width) of index key | 4,096 bytes when page size is 16 KB (limited to 1/4 of database page size) | 252 bytes |
| IMPORTANT: Limit decreases for character columns when character set is multi-byte; non-binary collation further reduces limit. | ||
| 每数据库最大索引个数 | 4,398,046,511,104 | Same |
Data Type Specifics
| Name | Size | Range/Precision | Description |
| Varchar(n) | n chars | 1 to 32767 bytes | Variable length char or text string. NB, multi-byte character sets reduce number of possible characters proportionately |
| Smallint | 16 bits | -2^15 to 2^15-1 | Signed short (word) |
| Integer | 32 bits | -2^31 to 2^31-1 | Signed long (longword) |
| Float | 32 bits | 3.4 x 10^-38 to 3.4 x 10^38 | Accurate to 7 digits |
| Double Precision | 64 bits | 1.7 x 10^-308 to 1.7 x 10^308 | Accurate to 15 digits |
| Timestamp | 64 bits (2 X 32 bits) |
1 Jan 100 CE to 28 Feb 32768 CE | Includes time and date as two 32-bit structures |
| Date | 32 bits | 1 Jan 100 CE to 28 Feb 32768 CE | Date only. Time part is not stored. |
| Time | 32 bits | 0:00 to 23:59.9999 | |
| BLOB | <32GB | — | Stores data of variable indeterminate size |
| Numeric (precision, scale) | Variable (16, 32, or 64 bits) |
specifies exactly precision digits of precision | Example: Numeric(10,3) holds numbers accurately in the following format: ppppppp.sss |
| Decimal (precision, scale) | Variable (16, 32, or 64 bits) |
specifies at least precision digits of precision | Example: Decimal(10,3) holds numbers accurately in the following format: ppppppp.sss |
Database Limits
| Item | Firebird 2.x | Firebird 1.5.x |
| Maximum size of database | Practically unlimited using multiple database files (largest known database is over 980 GB) | 32 TB using multiple files |
| Maximum size of one database file | Multiple terabytes on most platforms; limited by file systems (4 GB or 2 GB on some platforms) | Same |
| Maximum number of database files | 64,535 | Same |
| Maximum number of tables | 64,535 | Same |
| Maximum size of one table | ~32 TB | ~36 GB |
| Maximum size of external table file | 2 GB | Same |
| Maximum number of rows per table | > 16 Billion (not been measured beyond this) | ~4 Billion |
| NOTE: 1 Billion is 1024³ | ||
| Maximum row size | 65,536 bytes (64 KB) | Same |
| Maximum database page size | 16 KB | Same |
| NOTE: Page size (PAGE_SIZE) can be 1024, 2048, 4096, 8192 or 16384. Size 1024 is not recommended. | ||
| Maximum number of columns per table | Depends on data types used. (Example: 16,384 INTEGER (4-byte) values per row.) | |
| NOTE: 8-byte ID is stored for each BLOB or ARRAY reference; size of BLOB or ARRAY data is not counted in row size. | ||
| Maximum number of indexes per table | 65,535 | Same |
| Maximum size (total width) of index key | 4,096 bytes when page size is 16 KB (limited to 1/4 of database page size) | 252 bytes |
| IMPORTANT: Limit decreases for character columns when character set is multi-byte; non-binary collation further reduces limit. | ||
| Maximum number of indexes per database | 4,398,046,511,104 | Same |
Data Type Specifics
| Name | Size | Range/Precision | Description |
| Varchar(n) | n chars | 1 to 32767 bytes | Variable length char or text string. NB, multi-byte character sets reduce number of possible characters proportionately |
| Smallint | 16 bits | -2^15 to 2^15-1 | Signed short (word) |
| Integer | 32 bits | -2^31 to 2^31-1 | Signed long (longword) |
| Float | 32 bits | 3.4 x 10^-38 to 3.4 x 10^38 | Accurate to 7 digits |
| Double Precision | 64 bits | 1.7 x 10^-308 to 1.7 x 10^308 | Accurate to 15 digits |
| Timestamp | 64 bits (2 X 32 bits) |
1 Jan 100 CE to 28 Feb 32768 CE | Includes time and date as two 32-bit structures |
| Date | 32 bits | 1 Jan 100 CE to 28 Feb 32768 CE | Date only. Time part is not stored. |
| Time | 32 bits | 0:00 to 23:59.9999 | |
| BLOB | <32GB | — | Stores data of variable indeterminate size |
| Numeric (precision, scale) | Variable (16, 32, or 64 bits) |
specifies exactly precision digits of precision | Example: Numeric(10,3) holds numbers accurately in the following format: ppppppp.sss |
| Decimal (precision, scale) | Variable (16, 32, or 64 bits) |
specifies at least precision digits of precision | Example: Decimal(10,3) holds numbers accurately in the following format: ppppppp.sss |
