{"id":1232,"date":"2015-01-06T14:00:18","date_gmt":"2015-01-06T14:00:18","guid":{"rendered":"https:\/\/ibex.tech\/visualcpp\/?p=1232"},"modified":"2022-02-17T06:24:03","modified_gmt":"2022-02-17T06:24:03","slug":"datetime","status":"publish","type":"post","link":"https:\/\/ibex.tech\/visualcpp\/databases\/sqlite\/columns\/datetime","title":{"rendered":"DateTime"},"content":{"rendered":"

\nhttps:\/\/www.sqlite.org\/lang_datefunc.html<\/a>\n<\/p>\n

\nReading DateTime In Select Statements
\n<\/h4>\n

\nYou need to specify you want the value returning in a DateTime format or you can just get the year portion returned!\n<\/p>\n

\r\n\r\n\tCommand1->CommandText = "SELECT datetime(LogDateTime) as LogDateTime, SomeOtherColumnName FROM MyTable";\r\n<\/code><\/pre>\n
\n \n<\/p>\n
\nFaster Searches Based On Date
\n<\/h4>\n
\nOne nice and simple solution is to store dates as an intiger using this format:\n<\/p>\n
\nYYYYMMDD, so 1st Jan 2015 would be 20150101\n<\/p>\n
\nThen when performing select queries SQLite only has to work with integers not strings.\n<\/p>\n
\nConvert C++ DateTime to String for SQLite
\n<\/h4>\n
\nSQLite does not have a storage class set aside for storing dates and\/or times. Instead, the built-in Date And Time Functions of SQLite are capable of storing dates and times as TEXT, REAL, or INTEGER values:\n<\/p>\n
\nTEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").
\nREAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic Gregorian calendar.
\nINTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC. \n<\/p>\n
\r\n\r\nString ^DateTimeString = LogDateTime.ToString("yyyy-MM-dd HH:mm:ss.fff");\r\n<\/code><\/pre>\n
\nDefault to now
\n<\/h4>\n
\r\n\r\nCREATE TABLE IF NOT EXISTS tbl1(id int primary key, dt datetime default current_timestamp);\r\n<\/code><\/pre>\n
\nThe DEFAULT constraint specifies a default value to use when doing an INSERT. The value may be NULL, a string constant, a number, or a constant expression enclosed in parentheses. The default value may also be one of the special case-independant keywords CURRENT_TIME, CURRENT_DATE or CURRENT_TIMESTAMP.\n<\/p>\n
\nIf the value is NULL, a string constant or number, it is inserted into the column whenever an INSERT statement that does not specify a value for the column is executed. If the value is CURRENT_TIME, CURRENT_DATE or CURRENT_TIMESTAMP, then the current UTC date and\/or time is inserted into the columns.\n<\/p>\n
\nFor CURRENT_TIME the format is HH:MM:SS.
\nFor CURRENT_DATE it is YYYY-MM-DD.
\nFor CURRENT_TIMESTAMP it is "YYYY-MM-DD HH:MM:SS"<\/p>\n","protected":false},"excerpt":{"rendered":"
https:\/\/www.sqlite.org\/lang_datefunc.html Reading DateTime In Select Statements You need to specify you want the value returning in a DateTime format or you can just get the year portion returned! Command1->CommandText = "SELECT datetime(LogDateTime) as LogDateTime, SomeOtherColumnName FROM MyTable";   Faster Searches Based On Date One nice and simple solution is to store dates as an intiger using this […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[106],"tags":[],"class_list":["post-1232","post","type-post","status-publish","format-standard","hentry","category-columns"],"_links":{"self":[{"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/posts\/1232","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/comments?post=1232"}],"version-history":[{"count":8,"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/posts\/1232\/revisions"}],"predecessor-version":[{"id":1284,"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/posts\/1232\/revisions\/1284"}],"wp:attachment":[{"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/media?parent=1232"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/categories?post=1232"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ibex.tech\/visualcpp\/wp-json\/wp\/v2\/tags?post=1232"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}