-- Define an associative array of strings. TYPE calendar_table IS TABLE OF VARCHAR2(9 CHAR) INDEX BY BINARY_INTEGER; -- Declare and construct a varray. month MONTHS_VARRAY := months_varray('January','February','
This function opens a new database connection using the parameters taken from two NULL-terminated arrays. The first, keywords, is defined as an array of strings, each one being a key word. The second, values, gives the value for each key word. Unlike PQsetdbLogin below, the parameter set...
(PLpgSQL_expr)); /* 注意new已经在plpgsql_Datums数组中了,最后不需要返回 */ /* 下面在做一些调整,就可以结束了 */ /* Note: refname has been truncated to NAMEDATALEN */ cp1 = new->refname; cp2 = buf; /* * Don't trust standard_conforming_strings here; * it might change before we ...
} /* macros for representing SQLSTATE strings compactly */ #define PGSIXBIT(ch) (((ch) - '0') & 0x3F) #define PGUNSIXBIT(val) (((val) & 0x3F) + '0') #define MAKE_SQLSTATE(ch1,ch2,ch3,ch4,ch5) \ (PGSIXBIT(ch1) + (PGSIXBIT(ch2) << 6) + (PGSIXBIT(ch3) << 12) +...
Bit strings are strings of l's and 0's. They can be used to store or visualize bit masks. There are two SQL bit types: bit(n) and bit varying(n), where n is a positive integer. CREATE TABLE test (а BIT(3)定长, b BIT VARYING(5));变长 INSERT INTO test VALUES (B'101', ...
摘自:http://www.enmalvi.com/2022/10/28/postgresql-patroni/ 阅读完需:约 125 分钟 当单机的PG数据库无法满足企业需求的时候,那么就要寻求其他的解决方案,为单机的数据库升级改造,建立HA高可用集群数据库,也可以是分布式的集群数据库,这里简单的
说明:Number of bits in string 计算字符串的位数 例子:bit_length('jose') = 32 函数:char_length(string) or character_length(string) 说明:Number of characters in string 计算字符串中字符个数 例子:char_length('jose') = 4 函数:lower(string) ...
如果你关掉了standard_conforming_strings,你在文串常量中写的任何反斜线都需要被双写。 请注意反斜线在串文本里已经有特殊含义了,所以如果你写一个 包含反斜线的模式常量,那你就要在 SQL 语句里写两个反斜线。 因此,写一个匹配单个反斜线的模式实际上要在语句里写四个反斜线。 你可以通过用 ESCAPE 选择一个不...
This release also introduces support for CPU acceleration using SIMD for both x86 and ARM architectures, including optimizations for processing ASCII and JSON strings, and array and subtransaction searches. Additionally, PostgreSQL 16 introduces load balancing to libpq, the client library for PostgreSQL....
PostgreSQL offers your users a range of indexing techniques, including B+ tree index, Generalized Inverted Index, and Generalized Search Tree, in addition to full-text searching for string searches and strings of vector operations. Flexibility PostgreSQL is compatible with an array of the foremost ...