select '1' = any(string_to_array( array_to_string( array(select stu_id from student),',') ,',')); -- array_to_string用法 -- array() 把查询出来的name字段转换为array数组 -- array_to_string(’数组‘,'/')把数组转化为字符串,并用‘,'连接(使用提供的分隔符连接数组元素) select stu_...
PostgreSQL provides various array functions such asARRAY_APPEND(), ARRAY_TO_STRING(), ARRAY_REPLACE(), etc.STRING_TO_ARRAY()is one of them. Each array function serves a unique functionality. For instance, the STRING_TO_ARRAY() function converts a string into an array. This write-up will ...
说明:Convertstringtodest_encoding. The original encodingisspecifiedbysrc_encoding. The string must be validinthis encoding. Conversions can be definedbyCREATECONVERSION. Also there aresomepredefined conversions. SeeTable9-7foravailable conversions. 转换字符串编码,指定源编码与目标编码 例子:convert('text_...
String[] canada = {"Montreal", "Toronto", "Vancouver"}; String[] uk = {"London", "Birmingham", "Oxford"}; /* Convert String[] to java.sql.Array using JDBC API */ Array arrayUSA = conn.createArrayOf("text", usa); Array arrayCanada = conn.createArrayOf("text", canada); Array ...
convert(string using conversion_name) text 使用指定的转换名字改变编码。 convert('PostgreSQL' using iso_8859_1_to_utf8) 'PostgreSQL' lower(string) text 把字串转化为小写 lower('TOM') tom octet_length(string) int 字串中的字节数 octet_length('jose') 4 overlay(string placing string from int ...
Fixed issues with DATEPART(), DATENAME(), DATEDIFF() and DATEADD() functions to convert string to datetime and to recognize mi units. Support for TRY_CONVERT() function. Fixed issue with using strict/lax jsonpath with arrays to avoid OPENJSON error: "syntax error at or near " " of jsonpat...
typarray:指向同类型的数组类型的Oid。typinput,typoutput:类型的输入输出函数,数据库进行对数字进行存储或者输出,首先由客户端获取数据 (一般为字符串 )进行转化,变为数据库能够使用的数据类型。输出函数亦然。typreceive,typsend:输入、输出转换函数,多用于二进制格式。typmodin,typmodout:对于变长的数据的输入、...
{ /* convert to short varlena -- no alignment */ data_length = VARATT_CONVERTED_SHORT_SIZE(val); SET_VARSIZE_SHORT(data, data_length); memcpy(data + 1, VARDATA(val), data_length - 1); } else { /* full 4-byte header varlena */ data = (char *) att_align_nominal(data, att...
函数：lower(string)说明：Convert string to lower case 转换字符串为⼩写 例⼦：bit_length('jose') = 32 函数：octet_length(string)说明：Number of bytes in string 计算字符串的字节数 例⼦：octet_length('jose') = 4 函数：overlay(string placing string from int [for int])说明：Replace ...
hasNext()) { String next = iter.next(); } // iter close is done by GC 执行器的每一个物理算子都会实现这三个函数。当 PostgreSQL 的 planner 输出一棵物理计划树以后,在执行器初始化阶段,执行器会从计划树根节点的物理算子开始,调用物理算子的初始化函数;这个物理算子的初始化函数又会递归调用其下层...