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https://dev.mysql.com/innodb-row-format.html
The variable-length part of the record header contains a bit vector for indicating NULL columns. If the number of columns in the index that can be NULL is N, the bit vector occupies CEILING(N/8) bytes. (For example, if there are anywhere from 9 to ... The row format of a table determines how its rows are physically stored, which in turn can affect the performance of queries and DML ...
https://dev.mysql.com/known-issues.html
Numeric calculations are done with BIGINT or DOUBLE (both are normally 64 bits long). The general rule is that bit functions are performed with BIGINT precision, IF() and ELT() with BIGINT or DOUBLE precision, and the rest with DOUBLE precision. You ... This section lists known issues in recent versions of ...
https://dev.mysql.com/mysql-cluster-ndbd-definition.html
The arbitrator can be selected from an availability domain in which no data nodes are present, or, if no such availability domain can be found, from a third availability domain. 32-bit operating systems are generally limited to 2−4GB per process; ... The [ndbd] and [ndbd default] sections are used to configure the behavior of the cluster's data ...
https://dev.mysql.com/account-names.html
For a host value specified as an IPv4 address, a netmask can be given to indicate how many address bits to use for the network number. A netmask typically begins with bits set to 1, followed by bits set to 0. MySQL account names consist of a user ...
https://dev.mysql.com/cast-functions.html
To override this, use the SIGNED or UNSIGNED cast operator to cast a value to a signed or unsigned 64-bit integer, respectively. Table 12.14 Cast Functions and Operators Name Description BINARY Cast a string to a binary string CAST() Cast a value ...
https://dev.mysql.com/charset-unicode.html
They can be encoded in a variable-length encoding using 8, 16, or 24 bits (1 to 3 bytes). They can be encoded in a fixed-length encoding using 16 bits (2 bytes). The UTF-8 (Unicode Transformation Format with 8-bit units) method for encoding Unicode ... The Unicode Standard includes characters from the Basic Multilingual Plane (BMP) and supplementary characters that lie outside the ...
https://dev.mysql.com/control-flow-functions.html
The second syntax returns the result for the first condition that is true. If no comparison or condition is true, the result after ELSE is returned, or NULL if there is no ELSE part. Note The syntax of the CASE expr described here differs slightly ...
https://dev.mysql.com/disk-issues.html
RAID N can be a problem if you have many writes, due to the time required to update the parity bits. NFS Version 2 clients can only access the lowest 2GB of a file (signed 32 bit offset). NFS Version 3 clients support larger files (up to 64 bit ...
https://dev.mysql.com/enterprise-encryption-functions.html
Supported algorithm values: 'RSA', 'DSA', 'DH' Supported key_len values: The minimum key length in bits is 1,024. This example creates a 2,048-bit DSA private key, then derives a public key from the private key: SET @priv = ... MySQL Enterprise ...
https://dev.mysql.com/glossary.html
The performance of inserts is a key factor in data warehouse systems that load millions of rows into tables, and OLTP systems where many concurrent connections might insert rows into the same table, in arbitrary order. This arbitrary, ... These ...
Document created the 26/06/2006, last modified the 26/10/2018
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