![]() The result is: use the SUBSTR() function just as in the previous examples. SUBSTR(email, INSTR(email, LENGTH(email) - INSTR(email, + 1) AS substring You'd like to display the substring that starts at the sign and ends at the end of the string, but you don't know the exact indexes or lengths. The length of the substring is 5 ( end_index - start_index + 1). This time, the second argument of the function is 2, since we want to start at index 2. The result is: use the SUBSTR() function just as in the previous example. You'd like to display the substring between indexes 2 and 6 (inclusive). >SUBSTR(email, 1, 7) will return the substrings of the values in the email column that start at the first character and go for seven characters. ![]() This means the first character has index 1, the second character has index 2, etc. Watch out! Unlike in some other programming languages, the indexes start at 1, not 0. The third argument is the length of the substring. The second argument is the index of the character at which the substring should begin. The first argument is the string or the column name. You'd like to display the first seven characters of each email. In the emails table, there is an email column. If you want localtime you have to convert to localtime.You have a column of strings, and you'd like to get substrings from them. │ updatedtimestamp │ substr(UpdatedTimestamp,7,4) || '-' || substr(UpdatedTimestamp,4,2) || '-' || substr(UpdatedTimestamp,1,2) || substr(UpdatedTimestamp,11) │ Sqlite> select updatedtimestamp, substr(UpdatedTimestamp,7,4) || '-' || substr(UpdatedTimestamp,4,2) || '-' || substr(UpdatedTimestamp,1,2) || substr(UpdatedTimestamp,11) from x Sqlite> insert into x values (strftime('%d/%m/%Y %H:%M:%S')) Sqlite> create table x(updatedtimestamp) Use ".open FILENAME" to reopen on a persistent database. Substr(UpdatedTimestamp,7,4) || '-' || substr(UpdatedTimestamp,4,2) || '-' || substr(UpdatedTimestamp,1,2) || substr(UpdatedTimestamp,11) SQLite version 3.34.0 11:31:14Ĭonnected to a transient in-memory database. So you need to "fix" your UpdatedTimestamp to the correct ordering and separators. SQLite3 uses a subset of ISO8601 so the format is YYYY-MM-DD HH:MM:SS If you change the ordering, then you cannot sort or compare (well, you can still do an equality compare, but not an ordering compare). In the datetime universe, the biggest thing is the year, then the month, then the day, then the hour, then the minute, then the second, then the various subparts of seconds. In order for such strings to sort (compare) properly they must be in big-endian order (biggest thing first, followed one after each by the next smaller thing). ![]() SQLite3 does not have a datetime data type - datetime data is stored as a text string. Where UpdatedTimestamp >= strftime('%d/%m/%Y %H:%M:%S', datetime('now', '-1 day'))Ĭan someone please point out where I'm going wrong here? Working within the confines of being limited on formatting data before it is inserted? (and also have a lot of historical data) For example, I've tried to convert datetime output into the same format to use for comparison, but this doesn't work. I'm also unable to order query output by date/time correctly. I'm unable to run a query that correctly selects all data from a specific date, or within a specific time period. The field the data is inserted into is a datetime data type. The format of the data I have is '%d/%m%Y %H:%M:%S' e.g. I have a table that I'm using to store datetime data. I've been struggling with a datetime problem on this database now for a couple of months and have yet to come up with a solution. I come from a background of Oracle and CA Ingres (remember that?!) databases and have recently started using sqlite3 for a small home project.
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